DETAILED LESSON PLAN (DLP)
IN GRADE 8 SCIENCE
FOR PUBLIC SECONDARY SCHOOLS
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In accordance to the implementation of Republic Act (RA) No. 10533 or the Enhanced
Basic Education Act of 2013, the Department of Education (DepEd) issues the enclosed Policy
Guidelines on Daily Lesson Preparation for the K to 12 Basic Education Program (DO. 42 s.
2016). This is to ensure the delivery of teaching and learning in schools and serves as a
guideline for the preparation of the Daily Lesson Log (DLL) or Detailed Lesson Plan (DLP).
This Detailed Lesson Plan (DLP) is a collaborative work of the selected public school
secondary science teachers through the guidance and assistance of the science head teachers
and spear-headed by Mr. Antonio P. Faustino, Jr. – Education Program Supervisor in Science.
The information provided in this material is designed to provide helpful information and structural
framework on the delivery of instruction and facilitation of learning in Grade 8 Science. The
teacher may choose to follow the prescribed lesson plans, modify the suggested activities and/or
construct and innovate his own personal detailed lesson plan (to be attached in the Daily Lesson
Log) suited to the learners. References found in this material are provided for informational
purposes only and do not constitute endorsement of any websites or other sources. Teachers
should be aware that the websites listed in this material may change.
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CONTENT: Force, Motion and Energy
CONTENT STANDARD: The learner demonstrates understanding of the Newton’s three laws of
motion and uniform circular motion.
PERFORMANCE STANDARD: The learner develops a written plan and implement a –
Newton’s Olympics.
LEARNING COMPETENCY CODE: S8FE-Ia-15
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Recall the concepts learned in Grade 7 Science about Force and Motion;
2. Describe how force is related to motion; and
3. Appreciate the relevance of the continuity of the topics from the previous to the
present grade level.
II. SUBJECT MATTER
A. Topic: Force and Motion
B. Concepts:
Motion is the changing of position or location. But motion requires a force to cause that
change. Force is just a fancy word for pushing or pulling. If you push or pull something,
then you are applying force to it. Force makes things change its state of motion or rest.
C. Materials:
Prepared activity sheets and pen
D. References:
1. Learner’s Material pp. 3-16
E. Process/ Skills:
Identifying, Recalling and Describing
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism and Collaborative
Engage: THE SORTING BAG
Inside a bag are phrases related to force and motion. The students will try to sort out these
phrases and put them under two categories:
Which words are related to Force? Which are to Motion?
FORCE
Physical strength (push or pull)
External effort
Causes a change in the object’s state of motion or rest
MOTION
Movement
Change in position or location
Explore: GROUP ACTIVITY
Try to recall the concepts you’ve learned from your previous grade level by identifying the
terms related to the given scenarios (see attached activity group activity no. 1 sheet).
Explain: After doing the above said activity, lead the students in discussing their answers to
the following questions below:
a. What is the primary factor that can change the motion of an object? (Answer: Force)
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b. What will be produced if a force is applied to an object? (Answer: Motion)
c. In your own words, how is force related to motion? (Answer: If an external effort is
applied or exerted to an object, it will produce motion or simply Force causes motion.)
Let the students cite at least 1 example of a day-to-day experience showing the
relationship of Force to Motion.
Elaborate:
Your basic knowledge about Force and Motion will deepen as we discuss further about
Balanced and Unbalanced Forces, Combining Forces, Laws of Motion, Work and Energy.
Evaluate:
Student’s scores in the activity will show if they have achieved the objectives for the day.
Group Activity Rubric
Indicators
 Activity sheet is answered neatly and legibly
 Answered in time
 Individually participated
 Well explained/defended
 Answers are complete
Scoring
5 - All indicators are met
4 - 4 of the given indicators are present
3 - 3 of the given indicators are met
2 - 2 of the given indicators are manifested
1 - Only 1 of the indicators is met
Group No.
Grade 8- Section:
Date:
Score:
GROUP ACTIVITY NO. 1
Direction: Recall the concepts you have learned from your previous grade level by identifying the terms related to the given
scenarios and definitions.
SCENARIOS
TERMINOLOGIES
DEFINITION OF TERMS
R
The external effort that causes
an object to undergo a certain
change in its state of motion or
rest. (push or pull)
1. A boy’s push made the cart
move forward
2. A spinning top
N
The change in position or
location making movement.
3. A car racing on a 10 kilometre
race track
D
A length of path an object
travels.
4. It is faster if I will take Area 1
from my house in going
to school
D
The shortest path between the
point of origin and the point of
destination
5. A moving car travels 5m/s
6. The baseball was hit and travelled
50 m/s going North
7. The car run fast from 10 km/hr
North to 50 km/hr North after
it passed through the
pedestrian lane
D
O
It tells how fast an object
moves.
It tells how fast an object moves
and in what direction.
(speed + direction)
T
The rate at which the velocity of
a moving object changes over
time.
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Guide Questions:
a. What is the primary factor that can change the motion of an object?
b. What will be produced if a force is applied to an object?
c. In your own words, how is force related to motion?
d. Give 1 example of a day-to-day experience showing the relationship of Force to Motion.
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Identify the forces acting on an object;
2. Describe the different types of forces; and
3. Examine the effects of balanced and unbalanced forces on the state of motion of an
object.
II. SUBJECT MATTER
A. Topic: Balanced and Unbalanced Forces
B. Concepts:
Types of Forces
1. Applied force is a force that is applied to an object by a person or another object.
2. Gravitational force is a force with which the earth, moon, or other massively large object
attracts another object towards itself.
3. Normal force is the support force exerted on an object that is in contact with another
stable object.
4. Friction force is the force exerted by a surface as an object moves across it or makes an
effort to move across it.
5. Tension force is the force that is transmitted through a string, rope, cable or wire when it
is being pulled in opposite directions
6. Balanced force are two forces acting in opposite directions on an object, and equal in
size.
7. Unbalanced force - are two forces acting on an object that is not equal in size.
C. Materials:
Concept strips, diagram, toy car and coin
D. References:
Books:
1.
Science Grade 8 – Learner’s Manual
2.
Science Grade 8 – Teacher’s Guide
3.
Hewitt, P. et al. Conceptual Physical Science Explorations
Websites:
1.http://www.physicsclassroom.com/class/newtlaws/u2l1d.cfm
2. http://www.physicsclassroom.com/class/newtlaws/Lesson2/Types- of-Forces
3. http://www.ehow.com/list_7459343_ten-different-types
E. Process/ Skills:
Identifying, Classifying and Describing
F. Values Integration: Awareness
III. LEARNING TASK:
Pedagogical Approach: Inquiry-based
Engage:
Before giving an illustration, the teacher will ask the students: Does force always result in
motion? Then, the teacher will place a toy car on top of the table/ on the floor and may ask the
following:
a. How can we make this object move? (Push or pull it)
b. While it is moving, can we make the toy car speed up or slow down? How? (Yes, by
pushing it to the same direction or pulling it to the direction different from its original motion)
c. Can we make it stop? How? (Yes by disrupting its motion or letting it stop by itself)
This activity shows that force allows an object to change position or location.
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Explore:
Ask the students to get a coin and place it on top of their desk and ask:
a. Will this coin move by itself? (No)
b. Is the coin at rest or in motion? (At rest)
c. If the coin is at rest, does it mean that there’s no force acting on it? (No)
This activity shows that even an object is at rest, still there are forces that are acting on it.
Explain:
1. The teacher will show some pictures illustrating the different types of forces.
2. The learners need to analyze the given pictures in order to identify which type of force it
describes.
Picture 1: A standing man (Normal Force)
Picture 2: A ripe fruit falls from a tree (Gravitational Force )
Picture 3: A boy trying to slide on grass wearing shoes and a boy trying to slide on grass
wearing snowblades (Friction Force)
Picture 4: A hammer hitting a nail (Applied Force)
Picture 5: A kite flying in the skies (Tension Force)
Elaborate:
Effects of forces in an object:
1. How will a balanced force affect an object? (Anytime there is a balanced force on an
abject, the object stays still or continues to move at the same speed and in the same
direction.)
2. How will an unbalanced force affect an object in motion? Unbalanced forces causes:
 a still object to move
 a moving object to speed up or slow down
 a moving object to stop
 a moving object to change direction
Evaluate:
Direction: Write B if the forces are balanced and U if it is unbalanced.
1. A stationary ball on top of the table- B
2. Moving leaves on the tree- U
3. A man hitting a ball with a baseball bat- U
4. A standing lady- B
5. A table that slides as it is pushed- U
6. A boy sitting on a chair – B
7. A girl pushing a cart – U
8. Earth revolving around the sun – B
9. Cue ball suddenly come to a stop – B
10. Basketball thrown from three-point area – U
IV. ASSIGNMENT:
Direction: Identify the type of force which causes the following underlined objects to travel along a
circular path.
1.
2.
3.
4.
5.
An eraser is tied to a string swung in a horizontal circle. - Tension force
The moon orbits the earth. - Gravitational force
A car makes a sharp right-hand turn along a level roadway. - Frictional force
A ball being thrown to the basket- Applied force
A man sitting on a chair- Normal force
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I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Describe all the forces acting on an object;
2. Determine if the forces are balanced or unbalanced by computing the net force;
3. Correlate the value of algebraic expression in computing the net force acting on an
object.
II. SUBJECT MATTER
A. Topic: Combining Forces
B. Concepts:
An object may be acted upon by several forces. For example, an object may be pushed and
pulled in different directions at the same time. To identify which of these forces would be able to
cause change in the motion of the object, it is important to identify all the forces acting on it. To
accurately describe the forces acting on an object, it is important to be familiar first with the
following terms: magnitude, direction, point of application, and line of action.
1. Magnitude – refers to the size or strength of the force. It is commonly expressed in Newton
(N)
2. Direction – indicates the source of the force.
3. Line of action – is a straight line passing through the point of application
4. Point of application – is where the force applied to the object.
5. Balanced force – is a force equal in magnitude, opposite in direction and lie in the same
line of action.
6. Unbalanced force - is not opposed by an equal and opposite force; intended to cause a
change in the object's state of motion or rest.
 Combining forces: to determine the net force. (combining forces is limited only to forces
that lie along the same line of action.) Algebraic signs + and – are used to determine the
direction of forces.
General Formula:
Fnet = F1 + F2
C. Materials:
Activity sheets, illustrations and ball pen
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
Websites:
1. http://quest.arc.nasa.gov/aero/wright/teachers/pdf/math/Computing_Net_Force.pdf
http://www.physicsclassroom.com/class/newtlaws/Lesson-2/Determining-the-Net-Force
E. Process/ Skills
Identifying, Describing and Problem-solving
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based and Collaborative
Engage:
Look at the given illustration, describe the forces acting on illustration A and illustration B.
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A
B
1. What are the forces acting on illustration A? how about in illustration B?
2. What is the state of motion of the object in illustration A? B?
3. Are the forces balanced or unbalanced in illustration A? B?
Explore: GROUP ACTIVITY
The learners will provide the answers to the given questions in each of the situation given in the
activity sheets. Learning skills such as describing, identifying and problem-solving about
combining forces will be exhibited.
Explain:
After the learners performed the activity, each of the group will have their presenter to explain
and discuss the answers of their group about the situations given about combining forces.
Groups 1 to 4 will explain their answer in situation no. 1.
Groups 5 to 7 will explain their answer in situation no. 2.
Groups 8 to 10 will explain their answer in situation no. 3
Elaborate:
In each of the presentation, the teacher will emphasize the importance of identifying and
describing the magnitude, direction, line of action, and point of application in computing the
net force acting on an object.
Evaluate:
Student’s scores in the activity will show if they have achieved the objectives for the day. (Note:
In each of the situation, the students could have five (5) points.
Group Activity Rubric
Indicators
 Activity sheet is answered neatly and legibly
 Answered in time
 Individually participated
 Well explained/defended
 Answers are complete
Scoring
5- All indicators are met
4- 4 of the given indicators are present
3- 3 of the given indicators are met
2- 2 of the given indicators are manifested
1- Only 1 of the indicators is met
Group No.
Grade 8- Section:
Date:
Score:
GROUP ACTIVITY NO.2 COMBINING FORCES
Direction: Read the given situation carefully. Provide the answer for the given questions in each of
the situation given.
Situation #1: An airplane is flying west. Its engines are creating a thrust force (
magnitude 4,000. A strong headwind is blowing to the east creating a drag force (
airplane of magnitude 1,000.
) of
) on the
Question #1: What is the net force of the airplane?
Question #2: In what direction will the airplane fly?
Question #3: Draw a picture of this event. Make sure you include the airplane, the wind,
arrows to represent the magnitudes, and the equation the gives the net
force. (Note: Draw one arrow for each 1,000 units of magnitude)
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I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Explain what inertia is;
2. Describe the relationship of mass, shape and volume to inertia; and
3. Cite some examples involving inertia.
II. SUBJECT MATTER
A. Topic: First Law of Motion – Inertia
B. Concepts
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Law of Inertia – “An object at rest will stay at rest, and an object in motion will stay in motion at
constant velocity, unless acted upon by an unbalanced force.”
Factors that influence inertia:
1. Mass of the object - the greater the mass, the greater is the inertia. Mass is more than an
indication of an object’s inertia. Mass is also a measure of how much material an object contains.
Mass depends on the number and the kinds of atoms making up the object.
(Mass is not volume – volume is a measure of space. Mass is measured in kilograms. How many
kilograms of matter an object contains and how much space the object occupies are two different
things. For example, equal size bags of cotton and rocks may have equal volumes, but very
unequal masses.
Mass is not weight – mass is a measure of the amount of matter in an object. Weight depends on
gravity. It is the force due to gravity that acts on an object’s mass.
2. Shape and volume
Explanation:
Shape – Observed rallies where demonstrators were hosed by water cannons? If they were
standing, they would easily be thrown back by water pressure. So rallyists sit down and curl,
changing their shape. When they change their shape their inertia also changes (increased).
Volume – Have you taken a ride on an airplane? When you ride a small airplane, you would
observe turbulence to be more noticeable than in a bigger plane. Rides will be bumpier because
lesser inertia makes the smaller plane more affected by air pockets.
C. Materials:
Coins, two glasses, concept strips and diagram
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
Websites:
1.http://swift.sonoma.edu/education/newton/newton_1/html/newton1.html
E. Process/ Skills:
Identifying, Describing and Explaining
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based and Collaborative
Engage:
Suppose that you have seen a rising smoke or a rock thrown and fell on the ground, how will
you explain the tendency of the smoke to keep on rising and the rock thrown to always fall on the
ground?
Explore:
The learners will perform a game-relay called “Coin Drop Relay”.
5 boys and 5 girls will try to thump the card to drop the coin in the glass. One player will
repeatedly do this until the last player does. The group who will be able to finish first will be the
winner.
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Explain:
1. What happened to the coin when the cardboard is thumped quickly? (When you thumped
the card quickly, the coin fell into the cup)
2. What do you think could be the reason why the coin fell into the cup instead of flying away
with the card? (Answers may vary depending on student’s guess.)
The coins did not fly away with the card instead it fell into the cup because of Sir Isaac
Newton’s First Law of Motion called Inertia.
3. In your own words, what is inertia?
(Answers may vary depending on the student)
The property of an object to resist (fight back) a change in its current state.
Elaborate:
Situation no. 1: Look at the illustration given, which is more difficult to push?
Situation no. 2: What happens when you kick an empty tin can? Now kick the same can filled
with rocks. Which is more difficult to kick?
Evaluate:
Direction: Read each situation carefully and give an explanation of what will occur or your point.
(Note: This is non-graded assessment)
1. Imagine a place in the cosmos far from all gravitational and frictional influences. Suppose an
astronaut in that place throws a rock. What will happen to the rock? Explain your answer.
2. Mac and Tosh are arguing in the cafeteria. Mac says that if he throws his jello with a greater
speed it will have a greater inertia. Tosh argues that inertia does not depend upon speed, but
rather upon mass. With whom do you agree? Why?
3. Ben is being chased through the woods by a bull moose which he was attempting to
photograph. The enormous mass of the bull moose is extremely intimidating. Yet, if Ben makes a
zigzag pattern through the woods, he will be able to use the large mass of the moose to his own
advantage. Explain this in terms of inertia.
**This evaluation is not graded. It only aims to encourage the learners to critically think of the
situation and explain their answer.
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Explain the relationship between force, mass and acceleration;
2. Solve problems about acceleration using the general formula: F = ma; and
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3. Associate the concepts of acceleration to daily activities.
II. SUBJECT MATTER
A. Topic: Second Law of Motion – Acceleration
B. Concepts:
Law of Acceleration – “The acceleration produced by a net force acting on an object is
directly proportional to the magnitude of the net force, is in the same direction as the net
force, and is inversely proportional to the mass of the object.”
With “a” as the acceleration, “F” as the force and “m” as the mass, let us express the law
mathematically using the proportionality symbol ( ∝),
a ∝ F = acceleration is directly proportional to force
a ∝ 1 = acceleration is inversely proportional to mass
m
F ∝ m = force is directly proportional to mass
C. Materials:
Diagram, concept strips, solving problems
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process/ Skills:
Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
Suppose that you dropped two objects in the same height but with different weights, one is
heavier than the other. Which one will fall faster? Heavier object? Lighter object? Both? Explain
why.
Explore:
Look at the illustration given, what are your observations?
Explain:
Based on the given illustration, the learners will present their observation by answering the
following questions:
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1. Describe the movement of the ball. Which ball moves fastest? Slowest?
2. Describe the amount of force exerted. Which one has the greatest amount of force
exerted? Lowest?
3. Based on the illustration, what is the relationship of the exerted force with how fast the ball
moves?
4. Based on the given activity, how is mass related to acceleration? How about force is
related to acceleration?
Elaborate:
Derivation of Formula
- Newton observed those ‘rules’ of Acceleration and came up with a Formula
Triangle method
F
m ma
• F = ma (Force = Mass x Acceleration)
 m = F ( Mass= Force ÷ Acceleration)
a
 a= F_ ( Acceleration= Force÷
Mass) m
or
a= vf - vi (Acceleration= Final velocity – Initial velocity)
t
time
 Units of Force, Mass & Acceleration.
-The units used for force are Newton (N) or kg.m/s2
-The units used for mass are kilograms (kg)
-The acceleration units are meters per second squared (m/s2)
Provide a sample problem.
Problem 1: I am a roller skater with a mass of 72 kg. If I am accelerating toward a wall at 3.7
m/s2, what will be the amount of force at which I hit the wall?
Follow the GRESA (Given, Required, Equation, Solution, Answer)
G: mass= 72 kg
Acceleration= 3.7 m/s2
R: F=?
E: F= ma
S: F= (72 kg) (3.7 m/s2)
A: F= 266.4 kg.m/s2 or 266.4 N
Evaluate:
1. Determine the accelerations that result when a 12 N net force is applied to a 3-kg object
and then to a 6-kg object.
Answer: a. 4 m/s2 b. 2 m/s2
2. A net force of 15 N is exerted on an encyclopedia to cause it to accelerate at the rate of 5
m/s2. Determine the mass of the encyclopedia. Ans. 3 kgs.
3. Suppose that a sled is accelerating at a rate of 2 m/s2. If the net force is tripled and the
mass is doubled, then what is the new acceleration of the sled? Answer: 3 m/s2 The
original value of 2 m/s/s must be multiplied by 3 (since a and F are directly proportional)
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and divided by 2 (since a and m are inversely proportional).
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4. Suppose that a sled is accelerating at a rate of 2 m/s2. If the net force is tripled and the
mass is halved, then what is the new acceleration of the sled? Answer: 12 m/s2 The
original value of 2 m/s/s must be multiplied by 3 (since a and F are directly proportional)
and divided by 1/2 (since a and m are inversely proportional).
5. What is the acceleration of a train that travels from 100 m/s to 120 m/s in 10 seconds?
Answer: 2 m/s2
6. A car is stopped at a red light. When the light turns green, the car speeds up to 80 m/s in
5 seconds. What is the acceleration of the car? Answer: 16 m/s2
(Note: The solving problems given in the evaluation are not graded. It is for the enriching the
process skills of the learners in identifying the given quantities, computing for the required
quantity and critically solving given problems.)
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I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Solve problems about acceleration using the general formula F = ma;
2. Enhance their skills in computing given problems; and
3. Answer the given problems with confidence.
II. SUBJECT MATTER:
A. Topic: Solving Problems – Acceleration
B. Concepts:
Law of Acceleration – “The acceleration produced by a net force acting on an object
is directly proportional to the magnitude of the net force, is in the same direction as
the net force, and is inversely proportional to the mass of the object.”
With “a” as the acceleration, “F” as the force and “m” as the mass, let us express the law
mathematically using the proportionality symbol ( ∝ ),
a ∝ F = acceleration is directly proportional to force
a ∝ 1 = acceleration is inversely proportional to mass
m
F ∝ m= force is directly proportional to mass
C. Materials:
Solving Problems, pen and paper
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process/ Skills
Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Explain:
F
m a
Let’s try to derive the formula out of this triangle, shall we?
 F = ma (Force = Mass x Acceleration)
 m = F ( Mass= Force ÷ Acceleration)
a
 a= F_ ( Acceleration= Force÷ Mass)
or m
a= vf - vi (Acceleration= Final velocity – Initial velocity)
t
time
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Elaborate:
Practice Exercise:
A net force of 15 N is exerted on an encyclopedia to cause it to
accelerate at the rate of 5 m/s2. Determine the mass of the
encyclopedia.
G: F= 15 N
a= 5 m/s2
R: m=?
E: m= F
a
S: m= 15N
5 m/s2
A: m= 3 kg
or 15 kg.m/s2
5 m/s 2
Evaluate:
Direction: Read each of the given problems carefully. Provide the answers to the problems in
your fillers using the GRESA method.
1. During a race, a sprinter increases from 5.0 m/s tp 7.5 m/s over a period of 1.25 seconds.
What is the sprinter’s average acceleration during this period? Answer: 2.0 m/s2
2. What is the speed of a rocket that travels 9000 meters in 12.12 seconds? Answer: 742.57
m/s
3. What is the speed of a jet plane that travels 528 m in 4 seconds? Answer: 132 m/s
4. How long will your trip take (in hours) if you travel 350 km at an average speed of 80
km/hr? Answer: 4.38 hrs.
5. How many seconds will it take for a satellite to travel 450 km at a rate of 120 km/s?
Answer: 3.75 seconds
6. A ball rolls down a ramp for 15 seconds. If the initial velocity of the ball was 0.8 m/s and
the final velocity was 7 m/s, what was the acceleration of the ball? Answer: 0.41 m/s2
7. A meteoroid changed velocity from 1.0 km/s to 1.8 km/s in 0.03 seconds. What is the
acceleration of the meteoroid? Answer: 26.67 km/s2
8. The space shuttle releases a space telescope into orbit around the earth. The telescope
goes from being stationary to traveling at a speed of 1700 m/s in 25 seconds. What is the
acceleration of the satellite? Answer: 68 m/s²
9. How much force is needed to accelerate a truck with a mass of 2000 kg at a rate of 3
m/s2? Answer: 6000 N
10. A 300N force acts on a 25 kg object. What is the acceleration of the object? Answer: 12
m/s2
Note: The teacher may use only five items from the given solving problems in the evaluation part
depending on the capacity of the learners.
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LEARNING COMPETENCY CODE: S8FE-Ia-16
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Describe how action and reaction forces affect the state of motion of an object.
2. Cite different application of the 3rd law of motion – interaction.
II. SUBJECT MATTER:
A. Topic: Third Law of Motion – Action and Reaction
B. Concepts:
Law of Interaction
“For every action, there is an equal and opposite reaction.”
Important Ideas:
 According to Newton, whenever objects A and B interact with each other, they exert forces
upon each other. When you sit in your chair, your body exerts a downward force on the
chair and the chair exerts an upward force on your body. There are two forces resulting
from this interaction - a force on the chair and a force on your body. These two forces are
called action and reaction forces.
Concrete Examples:
 Consider the propulsion of a fish through the water. A fish uses its fins to push water
backwards. In turn, the water reacts by pushing the fish forwards, propelling the fish
through the water. The size of the force on the water equals the size of the force on the
fish; the direction of the force on the water (backwards) is opposite the direction of the
force on the fish (forwards).
 Flying gracefully through the air, birds depend on Newton’s third law of motion. As the
birds push down on the air with their wings, the air pushes their wings up and gives them
lift.
C. Materials:
Plan 1
LCD Projector, white screen (manila paper as an alternative), laptop and extension
socket
Plan 2
Diagram, concept strips
Note: There were two sets of materials suggested just in case there is no source of
electricity available for the power point presentation.
D. References:
Books:
1.
Science Grade 8 – Learner’s Manual
2.
Science Grade 8 – Teacher’s Guide
3.
Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, Classifying and Integrating lesson in daily activities
18
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism and Collaborative
Engage:
Look at the given illustration, what have you observed?
(Answer: He can hit the massive bag with considerable force. But with the same punch he can
exert only a tiny force on the tissue paper in midair.)
Explore:
In the presentation of the teacher, the students will describe the given illustrations and identify
the action and reaction force by drawing an arrow.
Here some examples of the illustration:
A
B
C
D
Explain:
With the students’ observation, the students will explain each of the situation following the
given questions.
1.
2.
3.
4.
What are the common type of forces seen in each of the diagram?
Describe the direction of these forces.
In describing the direction of the forces, identify the action force and reaction force.
How will you relate your observation with the concepts of the 3rd law of motion?
Elaborate:
The teacher will divide the class into small groups. Then, the teacher will give situations or
scenarios to students and they will try to explain it in the concepts of the 3 rd law of motion.
19
1. Which is most important in winning in a tug-of-war; pulling harder on the rope, or pushing
harder on the floor?
2. How does a helicopter get its lifting force?
3. A boxer can hit a heavy bag with great force. Why can’t he hit a sheet of newspaper in
midair with the same amount of force?
4. Can you physically touch another person without that person touching you with the same
magnitude of force?
Evaluate:
Group Scoring Rubrics:
Indicators
 Outputs are presented
 Answered in time
 Individually participated
 Well explained/defended
 Answers are complete
Scoring
5 – All indicators are met.
4 – 4 given indicators are presented
3 – 3 given indicators are presented
2 – 2 given indicators are presented
1 – Only 1 indicator is presented.
Note: Learning Code: S8FE-Ib-17 – how body responds to changes in motion is already met in
the DLP provided for the 1st, 2nd and 3rd law of motion in the given applications and examples.
20
LEARNING COMPETENCY CODE: S8FE-Ib-18
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Compare the motion of the free falling object with the object in circular motion and
describe their differences.
2. Infer that circular motion requires the application of constant force directed toward the
center of the circle.
3. Associate the value of attraction in improving one’s social and communication skills.
II. SUBJECT MATTER:
A. Topic: Free fall and Circular Motion
B. Concepts:
Centripetal force – (from Latin centrum "center" and petere "to seek") is a force that makes
a body follow a curved path: it is generally the cause of circular motion.
Centrifugal force (Latin for "center fleeing") describes the tendency of an object following a
curved path to fly outwards, away from the center of the curve. It's not really a force; it
results from inertia i.e. the tendency of an object to resist any change in its state of rest or
motion. Centripetal force is a "real" force that counteracts the centrifugal force and
prevents the object from "flying out", keeping it moving instead with a uniform speed along
a circular path.
C. Materials:
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
Website:
1. https://www.google.com.ph/webhp?
source=search_app&gfe_rd=cr&ei=RWufU9qtFqvkmAWe-4GwCQ&gws_rd=ssl#
2. http://en.wikipedia.org/wiki/Centripetal_force
E. Process/ Skills:
Identifying, Describing and Analyzing
F. Values Integration: Appreciation of the revolution of the earth to the sun.
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
The teacher will ask the learners: is there a constant force needed for the rotation of the earth
on its axis and revolution of the earth to sun? Explain why or why not.
21
Explore:
The teacher will demonstrate an activity for free fall and circular motion.
Situation 1: Drop two books with different masses from the same
height.
Situation 2: Whirl an object tied to a string horizontally above your
head. Then observe what happens if you release the object.
Explain:
1. What have you observed in the activity?
2. How would you explain it?
Elaborate:
A free falling object is an object that is falling under the sole influence of gravity. Any object
that is being acted upon only by the force of gravity is said to be in a state of free fall. There are
two important motion characteristics that are true of free-falling objects:
 Free-falling objects do not encounter air resistance.
 All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s/s
When the only force acting on an object is GRAVITY, the object is said to be in FREE FALL.
In a free fall, the force of gravity is unbalanced. This causes an object to accelerate. For ever
second an object is falling near the surface of the Earth, its velocity increases by 9.8 m/s. All
objects in free fall accelerate at the same rate (because mass does not matter).
Satellites follow a curved path around the Earth. Satellites orbit around the Earth. It
continually fall toward the Earth. Because the Earth is curved, even though satellites are falling
they continue to move around it. A force that causes an object to move in a circular path is a
centripetal force.
Evaluate:
Let’s say you and your classmates were in the amusement park for an instance, Enchanted
Kingdom. Create a list of rides that exhibits relationship in free fall object and uniform circular
motion.
Note: Learning Code: S8FE-Ib-19 is already met in the DLP provided for the 1st, 2nd and 3rd law
of motion in the given applications and examples. The teacher might choose to construct another
DLP (detailed lesson plan) for this learning competency.
22
CONTENT: Work, Energy and Power
CONTENT STANDARD: The learner demonstrate an understanding of work using constant
force, power, gravitational, potential energy, kinetic energy and elastic potential energy.
PERFORMANCE STANDARD: The learner proposes ways to increase the amount of work done
in a certain period.
LEARNING COMPETENCY CODE: S8FE-Ic-20
LESSON 9
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Relate the concept of work with the concepts of force.
2. Solve problems about work using the formula: W = F x d and other derivation.
3. Correlate the value of being industrious in doing daily task.
II. SUBJECT MATTER:
A. Topic: Work
B. Concepts:
Work is done when the force (F) applied to the object causes the object to have a
displacement (d) in the same direction as the force applied. The symbol for work is a
capital W. The work done by a force can be calculated as
C. Materials:
Concept strips, diagram, illustrations about work
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
Website:
1. http://physics.bu.edu/~duffy/py105/Energy.html
2. http://www2.franciscan.edu/academic/mathsci/mathscienceintegation/MathScienceInt
egation-1011.htm
3. http://www.physicsclassroom.com/class/1DKin/Lesson-6
E. Process/ Skills: Identifying, Classifying, and Problem solving
23
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
A large marble is dropped in an inclined plane and hit the small marble at the bottom. Then,
the activity is repeated but this time instead of dropping the large marble the small marble is
dropped and the large marble is the one at the bottom. Give your observation in this illustration.
1. What happened when the large marble hit the small marble? How about the small marble
hitting the large marble?
2. What is being transferred in the illustration given?
3. Do you think there is work done on the object?
Explore:
The teacher will give an activity about work. The title of the activity is “Is there work done?” In
this activity, pictures are provided. The students will answer and explain whether the given
picture is an example of work or not.
Explain:
The students will explain why they answer “work” or “no work” in each of the given picture.
After that, they will answer the following guide questions:
1. What is work?
2. What is the unit for work?
3. What is energy?
4. Could we consider that there is work done on an object if the direction of the force and
movement of the object are not the same?
Elaborate:
The teacher will now elaborate the concept about work. He will emphasize that “work is done
only when force applied on the object causes the object to have a displacement in the same
direction as the direction of the force or the component of the force.”
Sample Problem:
A large semi-truck is moving a house from one lot to another. The amount of force required to
move the house horizontally a distance of 73.2 meters is 3,500 Newtons. How much work will be
done on the house?
Given: F = 3,500 Newtons; d = 73.2 meters
Required: W = ?
Equation: W = F x d
Solution: W = F x d
= 3,500N x 73.2 meters
Answer: W = 256,200 Joules
Evaluate:
1. Calculate the amount of work done when moving a 567N crate a distance of 20 meters.
Ans.11340 J
2. If it took a bulldozer 567.6 joules of work to push a mound of dirt 30.5 meters, how much
force did the bulldozer have to apply? Ans. 18.61 N
3. A frontend loader needed to apply 137N of force to lift a rock. A total of 223 joules of work
was done. How far was the rock lifted? Ans. 1.63 meters
4. A young boy applied a force of 2550N on his St. Bernard dog who is sitting on the boy’s
tennis shoes. He was unable to move the dog. How much work did he do trying to push
the dog?
Ans. 0 Joule
5. If a weight lifter raises a barbell with a mass of 1257 kilograms doing 5023 joules of work,
what distance did he move the barbells? Ans. 0.41 meters
24
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Solve problems about work using the general formula W = F x d;
2. Enhance their skills in computing given problems; and
3. Answer the given problems with confidence.
II. SUBJECT MATTER:
A. Topic: Solving Problems - Work
B. Concepts:
Work is done when the force (F) applied to the object causes the object to have a
displacement (d) in the same direction as the force applied. The symbol for work is a
capital W. The work done by a force can be calculated as
C. Materials:
Solving problems, paper and pen
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process/ Skills: Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Explain:
Let’s try to derive the formula out of this triangle, shall we?
 W = F x d (Work = Force x displacement)
 F = W (Force = Work ÷ displacement)
d
 d = W_ (displacement = Work ÷ Force)
F
Elaborate:
25
Sample Problem No. 1:
A frontend loader needed to apply 137N of force to lift a rock. A total of 223 joules of work was
done. How far was the rock lifted?
G: F = 137N
W = 223 J
R: d = ?
E: d = W
F
S: d = 50 J = 50 N · m
5N
5N
A: d = 10 meters
Sample Problem No. 2:
If it took a bulldozer 300 joules of work to push a mound of dirt 20 meters, how much force did
the bulldozer have to apply?
G: W = 300 J
D = 20m
R: F = ?
E: F = W
D
S: F = 300 J = 300 N.m
20 m
20 m
A: F= 15 N or kg.m/s2
Evaluate:
Direction: Read each of the given problems carefully. Provide the answers to the problems in
your fillers using the GRESA method.
1. A fork lift moves 34 meters carrying a 1023 N box across the warehouse floor. How much
work is done by the fork lift? Answer: 34782 J
2. How much work is done by a person who uses a force of 27.5 N to move a grocery buggy
12.3 meters? Answer: 338.25 J
3. 55,000 Joules of work is done to move a rock 25 meters. How much force was applied?
Answer: 2200 N
4. You and 3 friends apply a combined force of 489.5 N to push a piano. The amount of
work done is 1762.2J. What distance did the piano move? Answer: 3.6 meters
5. If a long distance runner with a 596.82 N does 35,674 Joules of work during a portion of a
race, what distance will she cover during that portion? Answer: 59.77 meters
6. Children are sled riding on a hill. One little girl pulls her sled back up the hill and does
379.5J of work while pulling it back up the 17.3 meter hill. What amount of force did she
exert on the sled? Answer: 21.94 N
7. A fallen tree with a mass of 75 kg is lifted 2.75 meters. How much work is done? Answer:
2021.25 J
8. If it takes 68 Joules of work to push a desk chair 17 meters across a floor, what force
would be needed? Answer: 4 Newtons
26
LEARNING COMPETENCY CODE: S8FE-Id-22
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Identify the relationship between work and energy.
2. Explain the difference and similarities of potential and kinetic energy.
3. Give some concrete examples of these kinds of energy.
II. SUBJECT MATTER:
A. Topic: Potential and Kinetic Energy
B. Concepts:
The energy of a moving object is called energy of motion or kinetic energy (KE). The word
kinetic comes from the Greek word kinetikos which means moving. Kinetic energy
quantifies the amount of work the object can do because of its motion.
This shows that the work done in accelerating an object is equal to the kinetic energy
gained by the object.
You learned about the force of gravity. It is the force that the earth exerts on all
objects on its surface. It is always directed downward or towards the center of the earth.
Hence, when an object is lifted from the ground, the work done is against the force of
gravity. An object gains energy when raised from the ground and loses energy when made
to fall. The energy gained or lost by the object is called gravitational potential energy or
simply potential energy (PE).
C.
Materials:
Concept strips, diagram, illustrations about potential and kinetic energy
D. References:
27
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
Website:
1. http://physics.bu.edu/~duffy/py105/Energy.html
2. http://www2.franciscan.edu/academic/mathsci/mathscienceintegation/MathScienceIntegatio
n-1011.htm
3. http://www.physicsclassroom.com/class/1DKin/Lesson-6
E. Process Skills: Identifying, Classifying, and Problem solving
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Look at the diagram below, enumerate the different forms of energy.
28
ENERGY
Explore:
POTENTIAL VERSUS KINETIC ENERGY
Direction: Identify which is PE and which is KE based from the given definition.
1. A child jumping on the bedKE
2. A lamp turned on- KE
29
3. A sleeping child- PE
4. A ball on a basketball player’s hand- PE
5. A stretched rubber band-PE
6. A rolling soccer ball- KE
30
Explain:
 Emphasize that if you do work, you transfer energy from one object to another. Clarify that
it is energy and not force that is transferred when work is done.
 Relationship of work and energy
-When work is done, there is energy transferred. The body doing work loses energy while
the body on which work is done gains energy. In the bowling game, the one rolling the ball
loses energy while the ball gains energy. When the moving ball strikes the empty bottle it
loses energy while the plastic bottle gains energy.
 Different forms of energy
(All these forms of energy may be used or stored.)
a. Radiant energy from the sun
b. Chemical energy from the food you eat
c. Electrical energy from the outlets in your home
d. Mechanical energy refers to the energy an object has because of its motion
(Types: potential and kinetic energy)
d.1 Potential energy- Energy that is stored/ Energy at rest
d.2 Kinetic energy- Energy that is being used for motion/
Energy in motion
Elaborate:
PROBLEM on KE
1. What is the KE of a jogger with a mass of 65.0 kg traveling at a speed of 2 m/s2?
G: m= 65 kg
V= 2.5 m/s
R: KE=?
E: KE= mv2
2
S: KE= (65kg) (2 m/s) 2
2
= (65 kg) (4 m2/s2)
2
2
A: KE=130 kg.m /s2 or Joule
PROBLEM on PE
2. Find the potential energy of a light that has a mass of 13 kg and is 4m above the ground.
G: m= 13kg
g= 9.8 m/s2
h= 4 m
R: PE=?
E: PE= m x g x h
S: PE= (13kg)(9.8 m/s2)(4m)
31
A: PE= 509.6 kg.m2/s2 or Joule
Evaluate:
1. What is the kinetic energy of a 0.38 kg soccer ball that is traveling at a speed of 120 m/s?
Ans. 2736J
2. What is the mass of a baseball that has a kinetic energy of 105 J and is traveling at 10
m/s? Ans. 2.1 kg
3. What is the kinetic energy of a 0.50 kg ball that is travelling at a speed of 40 m/s? Ans.
400 J
4. An apple in a tree has a gravitational potential energy of 175 J and a mass of 0.36 g. How
high from the ground is the apple? Ans. 49.58 meters
5. A cart at the top of a 300 m hill has a mass of 40 kg. What is the cart’s gravitational
potential energy? Ans. 117600 J
6. A box with a mass of 12.5 sits on the floor. How high would you need to lift it for it to have
a GPE of 355J? Ans. 2.89 or 2.90 meters
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Solve problems about potential and kinetic energy with the given formula;
2. Enhance their skills in computing given problems; and
3. Answer the given problems with confidence.
II. SUBJECT MATTER:
A. Topic: Solving Problems - Potential and Kinetic Energy
B. Concepts:
The energy of a moving object is called energy of motion or kinetic energy (KE). The
word kinetic comes from the Greek word kinetikos which means moving. Kinetic energy
quantifies the amount of work the object can do because of its motion.
This shows that the work done in accelerating an object is equal to the kinetic energy
gained by the object.
You learned about the force of gravity. It is the force that the earth exerts on all
objects on its surface. It is always directed downward or towards the center of the earth.
Hence, when an object is lifted from the ground, the work done is against the force of
gravity. An object gains energy when raised from the ground and loses energy when made
to fall. The energy gained or lost by the object is called gravitational potential energy or
simply potential energy (PE).
32
C. Materials:
Concept strips, diagram, illustrations about potential and kinetic energy, solving problems
about PE and KE
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process/ Skills: Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Explain:
Present the derivations of the above formula.
KE = mv2
2
= unit of mass x unit of velocity
= (kg)(m/s)2
2
2
= kg.m /s2 or Joule
PE
=mxgxh
= unit of mass x acceleration due to gravity x unit of
height
= (kg) (9.8 m/s2)(m)
= kg.m2/s2 or Joule
• The teacher will provide a sample problem about potential and kinetic energy.
 Use the GRESA. Guide the students by asking the following:
What is the first step you took in solving the problem?
G. What are the given quantities?
R. What do you need to find?
E. What formula will you use?
S. How are you able to solve the problem?
A. What is your final answer?
Elaborate:
A. What is the KE of a 10 kg toy car with its velocity of 40 m/s?
G: m= 10 kg; V= 40 m/s
R: KE=?
E: KE= mv2
2
S: KE= (10kg)(40m/s)2
2
KE= 400 kg.m2/s2
2
A: KE= 200 kg.m2/s2 or Joule
B. Determine the potential energy of a 5 kg object when it is raised at 2m from the floor.
G: m= 5kg
33
g= 9.8 m/s2
h= 2m
R: PE=?
E: PE= m x g x h
S: PE= (5kg) (9.8m/s2)(2m)
A: PE= 98 kg.m2/s2 or Joule
Evaluate:
POTENTIAL ENERGY
1. If the mass of the loaded cart is 3.0 kg and the height of the seat top is 0.45 meters,
what is the potential energy of the loaded cart at height of the seat-top? Ans. 13.23 J
2. If a force of 14.7 N s used to drag the loaded cart along the incline for a distance of
0.90 meters, how much work is done on the loaded cart? Ans. 13.23 J
3. What is the PE of a 10 N book that is placed on a shelf that is 2.5 meters high? Ans. 25
J
4. Determine the amount of PE of a 5.0 N book that is moved to a height of 1.5 m. Ans.
7.5 J
KINETIC ENERGY
1. Determine the KE of a 625 kg roller coaster car that is moving with a speed of 18.3
m/s. Ans. 104,653.13 J
2. A 50 kg boy and his 100 kg father went jogging. Both ran at a rate of 5 m/s. Who had
more kinetic energy? Answer: boy – 625 J father – 1250 J
3. What is the KE of a 2000 kg boat moving at 5.0 m/s? Ans. 25,000 Joules
4. A 70 kg man is walking at a speed of 2.0 m/s. What is his kinetic energy? Ans. 140
Joules
5. A 1400 kg car is moving at a speed of 25 m/s. How much KE does the car have?
Answer: 437500 Joules
LEARNING COMPETENCY CODE: S8FE-Id-23
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Explain the importance of measuring the rate of doing work or using energy.
2. Calculate how much power is used in the given solving problems
II. SUBJECT MATTER:
A. Topic: Power
B. Concepts:
Power is the rate at which work is done. It is the work/time ratio. The standard metric unit
of power is the Watt. As is implied by the equation for power, a unit of power is equivalent
to a unit of work divided by a unit of time. Thus, a Watt is equivalent to a Joule/second.
C. Materials
Concept strips, diagram, activity about power
D. References
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process/ Skills: Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
34
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
As teenagers, we are so fond in watching anime with tremendous and incredible powers.
But how do we measure the amount of exerted power?
Explore:
The teacher will ask the students to compute for the power output of each member. The data are
indicated in the provided table below.
Name
Toriko
Luffy
Sanji
Kenshin
Mass
(Kg)
Weight
(N)
Height of stairs (m)
78
46
53
54
764.4
450.8
519.4
529.2
15
15
15
15
Time taken to
climb the stairs
(s)
9
4
6
7
Energy
Expended (J)
Power (J/s)
11,466
20,736.8
7,791
7,938
1,274
5,184.2
1,298.5
1,134
Explain:
1. Who among the group members had the highest power output?
2. What is the highest power output?
3. Who among the group members had the lowest power output?
4. What is the lowest power output?
5. What can you say about the work done by each member of the group? Did each member
perform the same amount of work in climbing stairs?
6. What factor/s determined the highest/lowest power output?
Elaborate:
1. How did you determine the group member which has the highest power output? Lowest
output?
2. What formula did you use in computing for the power?
3. What mathematical relationship has the following quantities have with the rate of power?
a. Force applied
b. Time taken to climb the stairs
Generalization:
Power is the rate at which work is done. It is the work/time ratio. The standard metric unit of
power is the Watt. As is implied by the equation for power, a unit of power is equivalent to a unit
of work divided by a unit of time. Thus, a Watt is equivalent to a Joule/second.
Evaluation:
Checking of the activity
The teacher will ask the students to volunteer in solving the problems about power and
write their answers on the board.
Analysis
1. What is the value of acceleration due to gravity? How did you solve for the weight?
35
2. How did you solve for the energy expended?
3. Are the given quantities on the board correct?
4. Did you encounter difficulties in analyzing the problems?
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Solve problems about power output with the given formula;
2. Enhance their skills in computing given problems; and
3. Answer the given problems with confidence.
II. SUBJECT MATTER:
A. Topic: Power
B. Concepts:
Power is the rate at which work is done. It is the work/time ratio. The standard metric unit
of power is the Watt. As is implied by the equation for power, a unit of power is equivalent
to a unit of work divided by a unit of time. Thus, a Watt is equivalent to a Joule/second.
C. Materials:
Concept strips, diagram, solving problems about power output
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
36
E. Process/ Skills: Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Explain:
Present the derivations of the above formula.
Power (Watts) = Work (Joules)
Time (seconds)
• The teacher will provide a sample problem about power.
 Use the GRESA. Guide the students by asking the following:
What is the first step you took in solving the problem?
G. What are the given quantities?
R. What do you need to find?
E. What formula will you use?
S. How are you able to solve the problem?
A. What is your final answer?
Elaborate:
Sample problem: If a swimmer does 3654 joules of work in 65 seconds,
what is the swimmer's power output?
G: W= 3654 J
t= 65 s
R: P=?
E: P= W
t
S: P= 3654 J
65 s
A: P= 56.21 J/s or Watts
Evaluate:
1. A mechanic uses a jack to lift a truck and does 7258J of work. If he lifts the truck .45
minutes, what was the power output? Answer: 268.81 Watts
2. How much work is done by a 125 watt blender that is crushing ice for 5 minutes? Answer:
37500 Joules
3. If a 60 watt light bulb does 216,000 joules of work, how long has it been burning? Answer:
3600 seconds
4. A set of pulleys lifts a piano and does 3,356 joules of work. If the piano is lifted in 75
seconds, how much power is used? Answer: 44.75 Watts
5. How much work is done in order to cook a bag of popcorn in a 500 watt microwave oven
for 5.5 minutes? Answer: 165000 Joules
6. What is the power of an electric toothbrush if it can do 755.8 joules of work in 75 seconds?
Answer: 10.07 Watts
7. A dock worker lifts a 375N crate a distance of 0.5m over his head in 2.3 seconds. What is
his power output? Answer: 81.52 Watts
8. An athlete is using the row machine in the gym. She does 3245 joules of work on the oars
in 72 seconds. What is her power output? Answer: 45.07 Watts
37
Post-Evaluation:
 Checking of the evaluation
The teacher will ask the students to volunteer in solving the problems about work and write
their answers on the board.
 Analysis
1. Are the given quantities on the board correct?
2. Is the formula used in solving the problem correct?
3. Did you encounter difficulties in analyzing the problems?
Note: Learning Code: S8FE-Ic-21 is already met in the DLP provided for energy and power. The
teacher might choose to construct another DLP (detailed lesson plan) for this learning
competency.
38
CONTENT: SOUND
CONTENT STANDARD: The learners understand the propagation of sound through solid, liquid
and gas.
PERFORMANCE STANDARD: The learners should be able to be familiarize with the
applications of the concept of sound.
LEARNING COMPETENCY CODE: S8FE-Ie-24
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Explain how sounds can be propagated through different media.
2. Compare and differentiate transverse wave and mechanical waves.
II. SUBJECT MATTER:
A. Topic: Propagation and Characteristics of Sound
B. Concepts:
Sound waves are examples of longitudinal waves. They also exhibit characteristic features
such as frequency, amplitude, wavelength, period and wave speed. The alternate pushing and
pulling mechanically exerts force on unit areas of air particles and thus creating pressure waves.
This alternating compressions and rarefaction make up the longitudinal waves like sound waves.
The speed of sound may differ for different types of solids, liquids and gases. For one,
the elastic properties are different for different materials. Thus, sound can travel faster in
mediums with higher elastic properties than in lower elastic properties. Another, the bond
strength between particles also affects the speed of sound. Thus, sound waves travel
faster in solids than in liquids and faster in liquids than in gases. While the density of a
medium also affects the speed of sound, the elastic properties have a greater influence on
wave speed. Another thing, the speed of sound is directly affected by the temperature of
the medium.
C. Materials:
Reading material about sound, illustration and diagram and concepts
D. Reference:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Discussing, Comparing and Differentiating
F. Values Integration: Awareness on the propagation of sound
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Based on the illustration, how would you describe sound which is a form of energy?
39
Explore:
Do you know the songs “May Be” and “Pay Phone?” How would you relate the science of
sounds to your daily lives? The teacher will provide reading materials about the sound. The
learners will make a thorough reading and answer the questions given about the sound.
Explain:
1. What is a sound?
2. How do we produce sounds?
3. Does sound travel/propagate through a medium?
4. Compare the transmission of sound through solids, liquids and gases.
5. Which of the medium will sound travel the fastest? Slowest?
Elaborate:
The teacher will explain the characteristics of sound and how sound is propagated in a certain
medium.
Evaluate:
Write “dobido-bido” if the statement is TRUE and “yeeha” if the statement is FALSE.
1.
2.
3.
4.
5.
A pulse of compressed air that is part of a sound wave is called refraction.
When an object is forced to vibrate at its natural frequency, resonance occurs.
Beats occur when two tuning forks at slightly different frequencies are sounded together.
Sound can travel through solids, liquids, and gases and even in a vacuum.
In order for sound from a speaker to reach a listener, air near the speaker must move to
the listener.
6. Almost everything that exists has a natural frequency.
7. Even steel bridge can collapse because of resonance.
8. The word “pitch” refers to the period of a sound wave.
9. If you strike a tuning fork and hold it on a table, the sound becomes relatively loud.
10. When an object is disturbed slightly and then left alone, it vibrates at its natural frequency.
READING MATERIAL ABOUT SOUND
Sound—it's almost impossible to imagine a world without it. It's probably the first thing you experience when you
wake up in the morning—when you hear birds chirping or your alarm clock bleeping away. Sound fills our days with
excitement and meaning, when people talk to us, when we listen to music, or when we hear interesting programs
on the radio and TV. Sound may be the last thing you hear at night as well when you listen to your heartbeat and
drift gradually into the soundless world of sleep. Sound is fascinating — let's take a closer look at how it works!
What is sound?
Sound is the energy things produce when they vibrate (move back and forth quickly). If you bang a drum,
you make the tight skin vibrate at very high speed (it's so fast that you can't usually see it), forcing the air all around
it to vibrate as well. As the air moves, it carries energy out from the drum in all directions. Eventually, even the air
inside your ears starts vibrating—and that's when you begin to perceive the vibrating drum as a sound. In short,
there are two different aspects to sound: there's a physical process that produces sound energy to start with and
sends it shooting through the air, and there's a separate psychological process that happens inside our ears and
brains, which convert the incoming sound energy into sensations we interpret as noises, speech, and music.Sound
is like light in some ways: it travels out from a definite source (such as an instrument or a noisy machine), just as
light travels out from the Sun or a light bulb. But there are some very important differences between light and
sound as well. We know light can travel through a vacuum because sunlight has to race through the vacuum of
space to reach us on Earth. Sound, however, cannot travel through a vacuum: it always has to have something to
travel through (known as a medium), such as air, water, glass, or metal.
The first person to discover that sound needs a medium was a brilliant English scientist known as Robert
Boyle (1627–1691). He carried out a classic experiment that you've probably done yourself in school: he set an
alarm clock ringing, placed it inside a large glass jar, and while the clock was still ringing, sucked all the air out with
a pump. As the air gradually disappeared, the sound died out because there was nothing left in the jar for it to
travel through.
How sound travels?
There is one crucially important difference between waves bumping over the sea and the sound waves that
40
reach our ears. Sea waves travel as up-and-down vibrations: the water moves up and down (without really moving
anywhere) as the energy in the wave travels forward. Waves like this are called transverse waves. That just means
the water vibrates at right angles to the direction in which the wave travels. Sound waves work in a completely
different way. As a sound wave moves forward, it makes the air bunch together in some places and spread out in
others. This creates an alternating pattern of squashed-together areas (known as compressions) and stretched-out
areas (known as a rarefactions). In other words, sound pushes and pulls the air back and forth where water shakes
it up and down. Water waves shake energy over the surface of the sea, while sound waves thump energy through
the body of the air. Sound waves are compression waves. They're also called longitudinal waves because the air
vibrates along the same direction as the wave travels.
Questions:
1. Based on the reading material that you’ve read, what is a sound?
2. How do sound travel? Does sound travel through a medium?
3. Describe and compare transverse waves and longitudinal waves.
4. Picture out how sound would travel through different mediums (solid, liquid and gas).
5. In your point of view, which of the medium will sound travel the fastest? Slowest? Explain why.
Reference: http://www.explainthatstuff.com/sound.html
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Distinguish reflection from refraction of sounds; and
2. Cite common applications of the two properties of sound.
II. SUBJECT MATTER:
A. Topic: Properties of Sound – Reflection and Refraction Sound
B. Concepts:
Sound can be reflected:
We call the reflection of sound an echo. A large fraction of sound energy is reflected
from a surface that is rigid and smooth. Less sound is reflected if the surface is soft and
irregular. Sound energy that is not reflected is either transmitted or absorbed.
Sound reflects from a smooth surface the same way light does – the angel of incidence is equal to
the angle of reflection. Reflected sound in a room makes it sound lively and full, as you have
probably noticed while singing in the shower. Sometimes when the walls, ceiling, and floor of a
room are too reflective, the sound becomes garbled. This is due to multiple reflections called
reverberations. On the other hand, if the reflective surfaces are too absorbent, the sound level is
low and the room may sound dull and lifeless. In the design of an auditorium or concert hall, a
balance must be achieved between reverberation and absorption. The study of sound properties
is called acoustics.
Sound can be refracted:
Sound waves bend when parts of the waves travel at different speeds. This occurs in
uneven winds or when sound is traveling through air of varying temperatures. This
bending of sound is called refraction. On a warm day, air near the ground may be warmer
than air above, and so the speed of sound near the ground increases. Sound waves
therefore tend to bend away from the ground, resulting in sound that does not seem to
carry well.
C. Materials:
Concept strips, diagrams, illustrations
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Discussing, Comparing and Differentiating
F. Values Integration: Awareness on the propagation of sound
41
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Figure 1
Look at the given illustration, what kind of event is being shown? Have you ever wondered why
open field concerts are usually held during nighttime? (Answers may vary.)
Explore:
Figure 2
Figure 3
Ask:
1. What have you observed:
a. as the ball hits the wall?(it bounced back)
b. to the spoon’s handle? (it looks bent)
2. If you will try to connect what you have observed from
the activity, how can you relate it to sound?
Probe further until you have extracted the concept that:
“SOUND CAN BOUNCE AND BEND”
Explain:
 Discuss the two properties of sound.
1. REFLECTION- is the bouncing back of sound waves as it hits a barrier/obstacle
a. Echo- is an example of a reflected sound
b. Reverberation- multiple reflections or echoes in a certain place/ repeated and
continuous echoing
2. REFRACTION- is the bending of sound waves when it moves from one medium to
another.
Elaborate
 Extend the discussion by including practical applications of
sound reflection and refraction.
On Sound Reflection
42
1. Bathroom singing
2. Use of ultrasound in
medicine
3. Use of sonar on mapping
the seafloor; on dolphins
and whales way of
communication; and on
bat’s way of food hunting
(Sonar- device used
for finding things by using
sound waves)
4. Knowledge of lessening
Echoes and reverberations
Theater and movie houses
On Sound Refraction
 Open field concerts held at night
Evaluate:
Tell whether the following situations represent REFLECTION or REFRACTION.
1. Bats use sonar waves to detect distances of the prey- Reflection
2. A man singing inside the bathroom producing reverberations- Reflection
3. Open field concerts are better done at night that at daytime- Refraction
4. With the use of high frequency sound ultrasound, the image of an unborn baby can be
projected on the monitor- Reflection
5. Dolphins and whales use sound waves in water as their method of communicationReflection
CONTENT:
Light
CONTENT STANDARD: The learner demonstrates understanding of some properties and
characteristics of visible light.
PERFORMANCE STANDARD: The learners discuss phenomena such as blue sky, rainbow, and red
43
sunset using the concept of wavelength and frequency of visible light.
LEARNING COMPETENCY CODE: S8FE-If-26
I OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Discuss the different theories that explain the properties and characteristics of light.
2. Construct a diagram summarizing the theories pertaining to light.
II. SUBJECT MATTER:
A. Topic: Theories about Light
B. Concepts:
see attached reading material about theories of light
C. Materials
Diagrams, illustration, reading material and pen
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Discussing, and Constructing
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
Have you seen a rainbow? What description could you give about the rainbow? How do
rainbows form? According to a song - “there’s a rainbow always after the rain,” is this statement
true?
Explore:
The teacher will provide reading materials about the sound. The learners will make a
thorough reading and answer the questions given about the theories about light.
Explain:
1. List down the four major theories that explained the nature and behavior of light.
2. Who is the proponent of the corpuscular theory of light? Provide a description of this
theory.
3. In the wave theory of light, who is the scientist that performed an experiment that served
as the evidence that light is a wave?
4. In the electromagnetic theory of light, explain what seems to be the problem if the light is
to believe as a wave.
5. Explain how Max Planck described the nature and behavior of light.
Elaborate:
There are four (4) major theories that explain the properties and behavior of light: corpuscular
theory, wave theory, electromagnetic wave theory and quantum theory.
Evaluate:
In a separate sheet of paper, construct a table summarizing the given theories about light.
44
A rubric will be used to evaluate the students.
Components
Completion of
the Task
Process
Neatness
Understanding
of the Task
Rating
40%
Actual Outcome
20%
25%
15%
100%
READING MATERIAL: Early Ideas about Light
1. Corpuscular Theory The understanding of light has developed mainly since the 1600’s. In 1666, the English
scientist Sir Isaac Newton discovered that white light is made up of all colors. Using a prism, he found that each
color in a beam of white light could be separated. Newton proposed the theory that light consists of tiny
particles that travel in straight lines through space. He called these particles corpuscles, and his theory became
known as the corpuscular theory.
2. Wave Theory
About the same time that Newton proposed his theory of light, the Dutch physicist and astronomer
Christian Huygens suggested that light consists of waves. He proposed the wave theory to explain the
behavior of light. The corpuscular and wave theories appear to be completely opposite, and scientists
argued about them for about 100 years. Then, in the early 1800s, the English physicist Thomas Young
demonstrated the interference of light. He showed that two light beams cancel each other under certain
conditions. Water waves also behave this way. Because it is hard to understand how interference could
occur with particles, most scientists accepted Young’s experiment as proof of the wave theory of light.
3. Electromagnetic Theory
In 1864, the British physicist James Clerk Maxwell proposed the mathematical theory of
electromagnetism. According to this theory, the influence that changing electric and magnetic fields have
on one another allows for the travel of waves. Maxwell’s theoretical waves had the exact mathematical
properties that had been measured for light. The vibrating electric charges that produce light are the
electric charges in the atom. Atomic physicists had already shown that these vibrating electric charges
exist. Maxwell’s work gave the wave theory of light a solid foundation.
Maxwell’s electromagnetic theory also did away with an idea that had stood in the way of
scientists’ acceptance of the wave theory for more than a century. Scientists felt they had to find the
medium (material) through which light waves travel. They reasoned that if light travels as waves, there
must be something for them to travel through, just as sound waves need air to travel through. But for
light, this something could not be matter, because light can travel in a vacuum. To get around this
difficulty, scientists suggested that the medium light traveled through was the ether.
All attempts to observe or measure the properties of the ether failed. Scientists became
increasingly convinced that the ether did not exist. Experiments conducted by Albert Michelson and the
American physicist Edward Morley in 1887 helped destroy the ether theory.
4. Quantum Theory of Light
In 1900, the German physicist Max Planck discovered an equation that matched experimental data
about the emission of light by a hot surface. Planck could not explain why the equation worked. But he
realized that it predicted that the tiny emitters of light on the surface can have only certain values of
energy. When energy is restricted to certain values, it is said to be quantized. In 1905, Einstein revealed
that light itself is quantized. Einstein reasoned that if light emitters can have only certain values of energy,
then the energy they emit as light will retain its quantized character. The light comes in tiny packets of
energy that are known as quanta. The concept of light as quantized energy explained how light behaves as
a particle in certain experiments, instead of as a wave. These particles of light came to be called photons.
In 1913, the Danish physicist Niels Bohr proposed that the energy of atoms was also quantized. When
energy is given to an atom, either by a collision or by shining light on it, the atom can accept only certain
values of energy. In this way, the atom becomes excited. When it de-excites, it must get rid of the extra
energy. One way it can do this is by emitting a photon that carries the energy away. Each type of atom
accepts a different set of energies. Thus, when atoms emit light, the photons from on type of atom differ in
energy from the photons from other types of atoms. A field of physics known as quantum mechanics is
the study of how atoms and light are quantized. It involves the fact that light and matter behave as
waves in some experiments and as particles in other experiments.
Analysis:
1. List down the four major theories that explained the nature and behavior of light.
45
2. Who is the proponent of the corpuscular theory of light? Provide a description of this theory.
3. In the wave theory of light, who is the scientist that performed an experiment that served as the evidence
that light is a wave?
4. In the electromagnetic theory of light, explain what seems to be the problem if the light is to believe as a
wave.
5. Explain how Max Planck described the nature and behavior of light.
6. What is quantum mechanics?
7. Create a table that summarizes the four major theories of light.
LEARNING COMPETENCY CODE: S8FE-If-27
I OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Identify how light disperse to form the colors of light;
2. Describe the hierarchy of colors of light in terms of frequency, wavelength, and energy;
and
3. Appreciate the beauty of everything with light dispersion.
II. SUBJECT MATTER:
A. Topic: Dispersion of Light
B. Concepts:
Dispersion is a special kind of refraction which provided us colors of light. Light of
different colors travels at different speeds in the prism which accounts for the different
degrees of bending or refraction.
C. Materials:
Diagrams, illustration
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Identifying, and Describing
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Ask:
1. Who among you have already seen a rainbow?
2. When can you see a rainbow? (We usually observe a rainbow after a rain shower.)
3. How is it formed? (The raindrops act as a prism separating the sunlight into bands of
colors. A rainbow is produced by reflection, refraction and dispersion of light when sunlight
strike drops of falling water which act as prisms )
Prism- a transparent glass or plastic object that usually has three sides and that separates the
light that passes through it into different colors
Explore: (3 minutes)
Say: Do you want us to make a rainbow?
Observational activity:
1. Turn off the lights to dim the classroom.
2. Hold a CD and shine it with a flashlight.
3. Observe what will happen.
Outcome: The reflected light will make fabulous
46
rainbow colors
Say: Did you enjoy watching how the rainbow color appear when white light strikes the CD? The
CD acted as a prism.
Explain
 How did the colors separate from the white light?
 When white light enters a prism, separation into different colors is observed. This
separation of colors through a prism is called dispersion.
Dispersion is a special kind of refraction which provided us colors of
light. Light of different colors travels at different speeds in the prism which
accounts for the different degrees of bending or refraction.
Elaborate
 Lead the students that:
a. Light is composed of colors of different frequencies and wavelength and the arrangement
of colors of light shows the order of the color’s corresponding energy.
b. ROYGBIV is the only part of the spectrum that can be
seen by the naked eye.
a. Using the diagram and the spectrum wheel, fill in the table
and answer the following questions: (20 mins)
Diagram
Spectrum Wheel
1.
2.
3.
4.
5.
Which color has the shortest wavelength? Violet
Which color has the longest wavelength? Red
Which color has the highest frequency? Violet
Which color has the lowest frequency? Red
Which color has the greatest amount of energy? Violet
Visible
Light
Frequen
cy
(Hz)
Wavelen
gth
(m)
Frequen
cy x
wavelen
gth
Energ
y
(eV)
47
Red
Orange
Yellow
Green
Blue
Violet
6. Which color has the least
amount of energy? Red
Evaluate
Have the students sing the song entitled Electromagnetic Spectrum. Let them give some
applications of light that are mentioned in the song.
Note: Learning Code: S8FE-If-28 is already met in the DLP provided for light. The teacher might
choose to construct another DLP (detailed lesson plan) for this learning competency.
48
CONTENT:
HEAT
CONTENT STANDARD: The learners understand heat and temperature and the effects of heat
on the body.
PERFORMANCE STANDARD: LEARNING COMPETENCY CODE: S8FE-Ig-29
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Distinguish between heat and temperature; and
2. Explain how heat and temperature are related.
II. SUBJECT MATTER:
A. Topic: Heat and Temperature
B. Concepts:
Unlocking of Terms:
1. Heat – is the transfer of energy between objects or places because of difference in
temperature. It is ‘thermal energy in transit’ and it is not contained in an object.
2. Thermal energy – is the energy that is actually contained in an object due to the motion
of its particles.
3. Temperature - a measure of the average kinetic energy of the particles in a sample of
matter, expressed in terms of units or degrees designated on a standard scale. Any of
various standardized numerical measures of this ability, such as the Kelvin, Fahrenheit,
and Celsius scale.
C. Materials:
Two glasses of water: cold, tap and warm
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Distinguishing, and Explaining
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Look at the illustration, what concepts of heat are being shown in this picture?
49
Explore:
Show two glasses of water: one that is cold and one that is warm. Ask the student to dip their
finger in each of the glass of water and describe the heat and temperature of water.
Questions:
1. Is the water warm or cold?
2. How did you know it is cold? Warm?
3. What do you think is the temperature of the water?
4. Why is it we could not tell accurately the temperature of water?
5. What could be the unit used to measure the temperature?
Explain:
Differentiate Heat and Temperature
Heat
Temperature
 Is the quantity of energy  Is the measure of hotness
absorbed or given off by an and coldness of an object
object
 Unit: Calorie
 Unit: Degree
 Instrument measuring
 Instrument measuring
heat: Calorimeter
temperature:
Thermometer
Elaborate:
 Relationship of heat and temperature
TEMPERATURE indicates the direction in which heat flows while HEAT is the actual energy
being transferred.
Evaluate:
Choose from the box below.
Degree
Temperature
1.
2.
3.
4.
5.
Heat
Thermometer
Calorie
Calorimeter
It is the quantity of energy absorbed or given off by an object. Answer: Heat
It is the unit of heat. Answer: Calorie
It is defined as the measure of hotness or coldness of a body. Answer: Temperature
The instrument used to measure temperature. Answer: Thermometer
The unit of Temperature. Answer: Degree
50
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Identify how heat transfer affects temperature, particle movement, object/material’s
size and phases of matter;
2. Demonstrate how changes in temperature, particles, size and phases of matter occur
due to heat transfer; and
3. Relate these concepts to the student’s day-to-day activities.
II. SUBJECT MATTER:
A. Topic: Effects of Heat Transfer
B. Concepts
Important Ideas!
 Heat is a transfer of (thermal) energy between objects or places due to temperature
difference.
 Heat transfers from an object of higher temperature to an object of lower temperature.
 Length, mass, and temperature are measured quantities. So just like the meter for length
and the gram for mass, we need units for temperature. This can be provided by three
different scales, namely Fahrenheit, Celsius and Kelvin.
 Heat is a form of energy and is measured in joules. It takes about 4.2 joules of heat to
change 1 gram of water by 1 Celsius degree. A unit of heat still common in the United
States is the calorie.
 Temperature is measured in degrees; heat is measured in joules.
C. Materials:
Group 1: Clear glass with hot water and metal spoon
Group 2: Clear glass with hot water
Group 3: Clear glass with cold water
Group 4: A jar that is tightly sealed (a mayonnaise jar)
Group 5: A cup of Ice cubes
Other materials needed:
LCD projector, extension wire and laptop, concept strips and diagram
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
E. Process/ Skills: Distinguishing, and Explaining
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage
Picture puzzle
EFFECTS OF
HEAT
TRANSFER
51
The puzzle will reveal the topic for the day: EFFECTS OF HEAT TRANSFER
Review: Each picture piece corresponds to a particular question
related to the previous lesson about introduction to heat and
temperature.
Q1: What is the unit for Heat? (Calorie)
Q2: What do you call the instrument used to measure Heat?
(Calorimeter)
Q3: What is the unit for Temperature? (Degree)
Q4: What do you call the instrument used to measure
Temperature? (Thermometer)
Explore
Introduce the effect of heat transfer by demonstrating each set
up.
Set up 1: A cup of hot water and a metal spoon
2: Cup with different water temperature and food dye
Cup A: With Tap water
Cup B: With Cold Water
Cup C: With Hot Water
3: A mayonnaise jar that is tightly sealed
4: Picture of Water
Explain
Expound the relationship of the set up shown above to each effect of heat transfer.
a. Temperature Change – Change in temperature (Set up 1)
 If heat is absorbed or given off by an object, the temperature
Changes
Object
absorbs heat ----- temperature rises (hot)
releases heat ------------------------------------------ temperature drops (cold)
b. Particle Movement- Change in the movement of particles
 The hotness or coldness of an object indicates how fast the
particles move
c. Thermal Expansion and Contraction- Change in size of the object
 Almost all objects/materials expand when heated and contract when cooled
High temperature (hot)
object/material expands (increase in
size- lengthens/enlarges)
Low temperature (cold)
object/material contracts (decrease in
size- shortens/ shrinks)
d. Phase Change- Change in phases of matter (solid, liquid and gas)
 Matter changes from one phase to another if heat energy is
absorbed or released.
HEAT IS TAKEN FROM (absorbed) THE ENVIRONMENT
SUBLIMATION
51
LIQUID
GAS
SOLID
MELTING
EVAPORATION
FREEZING
CONDENSATION
DEPOSITION
HEAT IS RELEASED (given off) FROM THE ENVIRONMENT
Elaborate:
The teacher explain further the effects of heat transfer using a powerpoint presentation.
Evaluate:
TRUE or FALSE.
Draw a
if your answer is TRUE and
if FALSE.
1. The lower the temperature of the water, the slower the scattering of the powdered milk.
2. When water is heated, it can change into ice.
3. Electric wires expand on cold days, and contract on hot days.
4. When the spoon absorbed heat, its temperature goes down.
5. If the metal is exposed to fire, it can mel
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Accomplish the crossword puzzle given about heat and temperature;
2. Explain the concepts of thermal expansion and its application; and
3. Cite the applications and examples of heat transfer in the life’s daily activities.
II. SUBJECT MATTER:
A. Topic: Thermal Expansion
B. Concepts
Unlocking of Terms:
1. Thermal expansion – is a tendency of matter to change in volume in response to change
in temperature.
2. Coefficient of thermal expansion - the degree of expansion divided by the change in
temperature.
Important Ideas!
Thermal expansion, the general increase in the volume of a material as its temperature is
increased. It is usually expressed as a fractional change in length or volume per unit temperature
change; a linear expansion coefficient is usually employed in describing the expansion of a solid,
while a volume expansion coefficient is more useful for a liquid or a gas.
C. Materials
Crossword puzzle, illustration and diagram, activity sheets about methods of heat transfer
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
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E. Process/ Skills: Discussing, Describing and Applying
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
The teacher will provide a copy of the crossword puzzle to the students. They will be
performing this activity by pairs. There are 20 words about heat and temperature that they need
to place in the puzzle.
Explore:
Activity 1:
After the learners accomplished the crossword puzzle, the teacher will provide illustration,
diagrams and situations in which the students will identify what method of heat transfer occurred
(conduction, convection and radiation).
Activity 2:
An illustration of two thermometers placed in A. hot water and B. cold water is shown to the
students. The learners will study and observe the connection of the heat and temperature in the
expansion and contraction of the liquid content of the thermometer.
Elaborate:
The teacher will expound the concepts about heat transfer specifically the importance of
applying the concepts of thermal expansion in constructing roads, bridges, etc.
Evaluate:
The class will be doing this evaluation by pairs. In a ½ crosswise, the students will be
enumerating at least five (5) examples of application of the concepts of thermal expansion.
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CONTENT:
ELECTRICITY
CONTENT STANDARD: The learners understand the current-voltage-resistance relationship,
electric power, electric energy and home circuit.
PERFORMANCE STANDARD: The learners should be able to apply the concepts in making a
series and parallel circuits.
LEARNING COMPETENCY CODE: S8FE-Ih-30
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Identify the basic parts of electric circuits.
2. Perform the activity – crossword puzzle about electricity.
II. SUBJECT MATTER:
A. Topic: Introduction to Electricity
B. Concepts
Main Electricity
Electric cells
Electric circuit
Electric components
C. Materials
Concept strips, crossword puzzle, diagram, LCD project (powerpoint presentation)
D. References:
Books:
1.
Science Grade 8 – Learner’s Manual
2.
Science Grade 8 – Teacher’s Guide
3.
Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, and Critical thinking skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Constructivism
Engage:
Think-Pair-Share
Look at the diagrams below:
A
B
C
1. What is/are needed for these appliances to operate?
2. Could you think of similar appliances used for the same purpose in
olden days?
Explore:
The class will be divided into small groups – each small group is consists of three (3)
members. Each group will receive a copy of the activity sheet – crossword puzzle about
electricity.
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Explain:
1. What are the terms that you have encountered in the activity?
2. How are these terms related to our topic?
3. By simply doing the activity, could you give a short, brief description of the following terms:
voltage, current and resistance?
Elaborate:
The teacher will explain the correlation of the words found in the crossword puzzle to the
concepts of electricity.
Evaluate:
A rubric will be used to evaluate the students.
Components
Completion of
the Task
Group Process
Neatness
Understanding
of the Task
Rating
40%
Actual Outcome
20%
25%
15%
100%
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Describe the electric current, voltage and resistance and cite their differences.
2. State the relationship of current, voltage and resistance.
II. SUBJECT MATTER:
A. Topic: Relationship of Current, Voltage and Resistance
B. Concepts
Every bit of matter, wires included, contains enormous numbers of electrons that swarm
about in random directions.
When they are set in motion in one direction, a net direction, we have an electric
current. The rate of electrical flow is measured in amperes.
When water flows in a pipe, there is more pressure on one end than the other. There
must be a pressure difference to keep the water flowing. Similarly for electric current.
Electrons flow in a wire only when a difference in electrical pressure exists. The name for
electrical pressure is voltage.
How much current there is depends on the voltage, and also on the electrical
resistance of the circuit. Electrical resistance is measured in units called ohms
C. Materials
Concept strips, diagram, LCD project (powerpoint presentation)
D. References
Books:
1.
Science Grade 8 – Learner’s Manual
2.
Science Grade 8 – Teacher’s Guide
3.
Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, and Critical thinking skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Inquiry-based
Engage:
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Look at the given illustration below.
questions
Give your observations and answer the following
How would describe illustration a? illustration b?
1. Compare the flow of water in illustration a and b.
2. Which of the two illustration will have a continues flow of water?
3. How is the illustration of the flow of water related to electricity?
Explore:
The class will be divided into five groups. Each group will study and give their observations in
the provided four (4) illustrations in order to explain the relationship (directly or inversely
proportional) between electric current, voltage and resistance
A
B
C
D
Explain:
1. What are your observations in the given four (4) illustrations?
2. In illustrations “a” and “b”, how would you describe the electric current, voltage and
resistance?
3. Provide a simple definition of your own for electric current, voltage and resistance based
on the illustration “a” and “b.”
4. In illustration “c” and “d,” what is the relationship between current and voltage? How about
current and resistance?
5. Give your generalization of the relationship between current, voltage and resistance.
Elaborate:
The teacher will expound the answers given by the group in the activity. Deeper concepts and
description about electric current, voltage and resistance will also be presented in the powerpoint
presentation of the teacher.
Evaluate:
Group Presentation Rubric
Criteria
Organization
- presentation of the observation were very
organized and clearly presented.
Teamwork/ Participation
- The group worked well with each other and
the task was shared equally among the
members of the group.
Score
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Content
Group members had a stronghold on the
content and it was thoroughly addressed.
Visual Materials
Visual materials were effectively used
throughout the presentation.
Note: Please see attached group presentation rubric for complete category of scoring the learners.
I. OBJEcTIVES:
At the end of the lesson, 80% of the students should be able to:
II. SUBJECT MATTER:
A. Topic: Solving Problems - Current, Voltage and Resistance
B. Concepts
C. Materials
Concept strips, diagram, solving problems about Ohm’s Law
D. References
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, Computing and Problem solving skills
F. Values Integration: Awareness
III. LEARNING TASK
Explain:
Present the derivations of the above formula.
Current (Amperes) = Voltage (Volts)
Resistance (Ohms)
• The teacher will provide a sample problem about ohm’s law.
 Use the GRESA. Guide the students by asking the following:
What is the first step you took in solving the problem?
G. What are the given quantities?
R. What do you need to find?
E. What formula will you use?
S. How are you able to solve the problem?
A. What is your final answer?
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Elaborate:
Sample Problem:
How much current flows through a lamp with a resistance of 60 ohms when the voltage across
the lamp is 12-V?
G: R = 60 ohms
V = 12 volts
R: I = ?
E: I = V
R
S: I = 12 volts
60 ohms
A: I = 0.2 Amperes
Evaluate:
1. What is the resistance of an electric frying pan that draws a current of 12 amperes when
connected to a 120 volts circuit? Answer: 10 volts
2. At 100,000 ohms, how much current will flow through your body if you touch the terminals
of a 12 volts batter? Answer: 0.00012 amperes
3. If your skin is very moist, so that your resistance is only 1000 ohms, and you touch the
terminals of a 12 volts battery, how much current do you receive? Answer: 0.012 amperes.
4. A 110 volt wall outlet supplies power to a strobe light with a resistance of 2200 ohms. How
much current is flowing through the strobe light? Answer: 0.05 amperes
5. A CD player with a resistance of 40 ohms has a current of 0.1 amps flowing through it.
Sketch the circuit diagram and calculate how many volts supply the CD player. Answer: 4
volts
6. A 120-volt power source supplies a lamp with a resistance of 192 ohms. What is the
current flow of the circuit? Answer: 0.625 amperes
Post-Evaluation:
 Checking of the evaluation
The teacher will ask the students to volunteer in solving the problems about ohm’s law and
write their answers on the board.
 Analysis
1. Are the given quantities on the board correct?
2. Is the formula used in solving the problem correct?
3. Did you encounter difficulties in analyzing the problems?
LEARNING COMPETENCY CODE: S8FE-Ii-31
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Describe a series and parallel circuits with the provided illustrations and diagrams.
2. Differentiate the connections of the two kinds of circuits.
3. Identify the advantages and disadvantages of the kinds of circuit.
II. SUBJECT MATTER:
A. Topic: Series and Parallel Circuits
B. Concepts
Simple circuit- a type of circuit composed only of wires, battery and 1 bulb
Multiple load circuit- a type of circuit composed of wires, battery and 2 or more bulbs.
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Two Types of Multiple Load Circuit
a. Series Circuit- a type of multiple load circuit having 1 pathway of current
b. Parallel Circuit- a type of multiple load circuit having 2 or more pathways of current
C. Materials
Concept strips, diagram, LCP projector, manila paper, pentel pen
D. References
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, Classifying, Collaborative skills
F. Values Integration: Awareness
III. LEARNING TASK
Engage:
Look at the provided illustrations and give your observations.
A
B
1. What are your observations in illustration “a”? illustration “b”?
2. Are these two illustrations the same? Why do you say so?
3. What are the parts showed in illustration “a”? how about in illustration “b”?
Explore:
The teacher will divide the class into five small groups. The task given is to draw the electric
symbols that they know and label it. Then, using the electric symbols that they have drawn; they
will collaborate and construct a diagram of series and parallel circuits. After the given time, the
class will have a group presentation about their outputs.
Explain:
1. What are the different electric symbols that your group had drawn?
2. Give the basic description or functions of the electric symbols that your group has
presented.
3. How were you able to come up with the diagram of the series and parallel circuits?
4. In your own words (based on your collaborations), what is a series circuit? Parallel
circuits?
Elaborate:
The teacher will continue in his powerpoint presentation to provide the learners an in-depth
discussion and explanation of the series and parallel circuits.
Evaluate:
There is a scoring rubric provided in the group presentation. Please see the attached scoring
rubrics.
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LEARNING COMPETENCY CODE: S8FE-Ii-33
I. OBJECTIVES:
At the end of the lesson, 80% of the students should be able to:
1. Construct functional models of a simple, series and parallel circuits;
2. Show their creativity and unity in making their projects as a group; and
3. Finish their circuit models on time.
II. SUBJECT MATTER:
A. Topic: Constructing Series and Parallel Circuit
B. Concepts
Simple circuit- a type of circuit composed only of wires, battery and 1 bulb
Multiple load circuit- a type of circuit composed of wires, battery and 2 or more bulbs.
Two Types of Multiple Load Circuit
a. Series Circuit- a type of multiple load circuit having 1 pathway of current
b. Parallel Circuit- a type of multiple load circuit having 2 or more pathways of current
C. Materials:
Refer to the activity
D. References:
Books:
1. Science Grade 8 – Learner’s Manual
2. Science Grade 8 – Teacher’s Guide
3. Hewitt, P. et al. Conceptual Physical Science Explorations
E. Process Skills: Identifying, Classifying, Collaborative skills
F. Values Integration: Awareness
III. LEARNING TASK
Pedagogical Approach: Collaborative
Engage:
Did you bring all the necessary materials for today’s project making?
Explore:
Each group is assigned to make their own circuit models.
Series circuit
Parallel circuit
Explain:
Explain the students the procedures of making their models.
1. Stick the two thumbtacks in the wooden tablet, about 3-4 cm apart from each other.
2. In cutting the wires, you must strip the plastic off on both ends using scissors. Place the
wire under each thumbtack. Connect the free end of the wire to a battery contact and the
free end of the other wire to the bulb holder. Connect the third wire from the bulb holder to
the other battery contact.
3. Open up the paper clip and thread it under one of the thumbtacks.
4. Move the other end of the paper clip and bring it into contact with the second thumbtack.
Then push the end of the paper clip away.
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Elaborate:
Assist the students in making the project. Give them safety reminders as they use cutter or
scissors.
Evaluate:
Students will be graded according to the following rubrics.
GRADING SYSTEM
Indicators
 Functional (bulbs light up, good wiring)
 Durable (do not easily collapse ,long battery life)
 Creatively and neatly made
 Members showed unity in making the product
 Submitted the product on time (on the day the product was made)
Rubrics
(100%) 5- All indicators are met
( 95%) 4- 4 of the given indicators are present
( 90%) 3- 3 of the given indicators are met
(85% ) 2- 2 of the given indicators manifested and/or for those who will submit late
(80%) 1- Only 1 of the indicators is met
(70%) 0- Did not meet any of the given criteria or for those who did not submit
Note: Learning Code: S8FE-Ii-32 is already met in the DLP provided for series and parallel
circuits. The teacher might choose to construct another DLP (detailed lesson plan) for this
learning competency.
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