TO
Module No. 2
Laws of Motion
Science 8
Quarter 1
(PHYSICS)
Prepared by: RICA VANESSA L. SUGUITAN
MOST ESSENT IAL LEARNING COMPETENCY
Investigate the relationship between the
amount of force applied and the mass of
the object to the amount of change in the
object’s motion.
What is common in the situations above?
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He introduced the idea of impetus
Aristotle
He introduced the
“Theory of Impetus”
John Philoponus
Impetus-driving force
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Theory of Impetus
“When impetus decreases,
the speed of an object
also decreases.
When that impetus is removed,
the object stops moving.”
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Developed the theory of Impetus
Jean Buridan
Motion is possible through a “mover”
that keeps the object moving
with power proportional
to the speed and mass of the object.
When the mover is removed,
the object stops moving.
He later named impetus as force.
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Presentation Title
He disagreed the idea of Aristotle
He claimed that even without a
continuous application of force,
an object can continue to move
Galileo Galilei
with constant speed
in a straight line provided there are
no outside forces acting on it.
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Sir Isaac Newton
Lived: 1642 - 1727
 English mathematician,
astronomer, and physicist
 One of the most influential
scientists of all time
 Laid foundation of
classical mechanics
 3 Laws of motion and
universal gravity
Newton’s Contributions
• * Calculus
• * Light is composed
of rainbow colors
• * Reflecting
Telescope
• * Theory of
Gravitation
Newton’s
Laws of Motion
Presentation Title
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Law
of
Inertia
What is
INERTIA?
Presentation Title
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Inertia is measured in terms of
mass.
An object having greater mass
has greater inertia
Agree or Disagree?
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A
B
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Newtown’s 1st Law of Motion
“Law of Inertia”
An object at rest will stay at rest
or an object in motion will stay in
motion and travel in straight line,
as long as no external net force
acts on it.
Inertia is exhibited when the
body moves forward as if to
continue moving.
Sudden acceleration will make
the body moves backward.
E
X
A
M
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E
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E
X
A
M
P
L
E
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Presentation Title
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Newton’s Second Law of Motion
Law of
Acceleration
What is
Acceleration?
ACCELERATION
It is the rate at which velocity
changes.
Object accelerates if its speed changes, if its
direction changes and if both speed and direction
changes.
FORCE
MASS
Newtown’s 2nd Law of Motion
“Law of Acceleration”
“The acceleration of an object
is directly proportional to the
magnitude of the net force
acting on it and is inversely
proportional to its mass.”
Newton’s
Second Law
Law of
Acceleration
Force equals mass
times acceleration
F = ma
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Like any other quantity, force has unit and is expressed
in Newton (N).
One Newton is defined as the amount of force
required to give a 1kg mass an acceleration
of
1m/s/s, or 1Newton (N) = 1kg/m²
Law of Acceleration
The formula is written as:
f= m x a
f= force
m=mass of an object
a= acceleration
Law of Acceleration
Sample Mathematical Problem:
Use G-RE-S-A method.
Suppose a grocery cart has a
mass of 0.45kg is push with a
force of 90N. What will be the
acceleration of the grocery cart?
Suppose a grocery cart has a mass of 0.45kg is push with a force
of 90N. What will be the acceleration of the grocery cart?
Given:
mass – 0.45kg
Required:
acceleration
Equation:
𝑭𝒏𝒆𝒕
a=
𝒎
Solution:
90N
a=
0.45kg
Answer:
a = 2 m/s²
Fnet - 90N
A net force of 15 N is exerted on an encyclopedia to cause it to
accelerate at a rate of 5 m/s2. Determine the mass of the encyclopedia
Given:
Acceleration– 5 m/s2
Required:
mass
Equation:
𝑭𝒏𝒆𝒕
m=
𝒂
Solution:
15N
m=
5 m/s2
Answer:
m= 3 kg
Fnet - 15N
Sample problem 3.
A box is pushed with an applied
force of 20 N parallel to the
floor. It accelerated at 1.50
m/s2 to the right. A parallel
applied force of 10 N on the
opposite side slowed down the
motion of the box. Neglecting
friction, what is the mass of the
box?
Given: 𝑎⃗=1.50 𝑚/𝑠2, to the right;
FA = 20 N, FB = 10 N;
Required: Mass
Equation:
Σ𝐹⃗=𝑚𝑎⃗
Solution:
Σ𝐹⃗=𝐹⃗𝑛𝑒𝑡=(+20 𝑁)+(−10 𝑁)=+10 𝑁;
+10 𝑁=𝑚(1.50 𝑚/𝑠 2 ) ;
m=
Answer: 𝑚=6.67 𝑘𝑔
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Presentation Title
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Newton’s Third Law of Motion
Law of
Interaction
Newtown’s 3rd Law of Motion
“Law of Interaction”
“For every action,
there is an equal and
opposite reaction.”
Newton’s 3rd law of motion tells us
four characteristics of forces.
Forces always occur in pairs (action and
reaction forces).
Action and reaction are equal in magnitude.
Action and reaction are opposite in direction.
 Action and reaction act on different bodies.
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Presentation Title
Presentation Title
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Throwing garbage on the river
would go back to the
community during the flood
season.
Law of Interaction
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Law of Inertia
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It is easier to push an
empty shopping cart
than a loaded one.
Law of Acceleration
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Law of Interaction
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The baseball is thrown
into the air after being
hit by the bat.
Law of Interaction
Law of Acceleration
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Presentation Title
When walking, your foot pushes
the ground backward, and the
ground pushes your foot
forward.
Law of Interaction
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Law
of
Inertia
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A runner who reaches the
finish line must continue
running for some time.
Law of Inertia
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Law of Acceleration
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Attendance Link
September 29,2021
https://forms.gle/DpDQt2
BD6LGxcRg86
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Weekly Task: Problem Solving
Performance Task 1: Isaac Newton’s Olympics
Summative Test 1: (google form)
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