Name __________________________________ Block _________ Date ______________
8th Grade Science
The critical scientific concepts developed in this standard include the following:

Matter is anything that has mass and occupies space. All matter is made up of small particles called atoms. Matter can exist as a
solid, a liquid, a gas, or plasma.

Matter can be classified as elements, compounds, and mixtures. The atoms of any element are alike but are different from atoms
of other elements. Compounds consist of two or more elements that are chemically combined in a fixed ratio. Mixtures also
consist of two or more substances, but the substances are not chemically combined.

Compounds can be classified in several ways, including:
- acids, bases, salts
- inorganic and organic compounds.

Acids make up an important group of compounds that contain hydrogen ions. When acids dissolve in water, hydrogen ions (H +)
are released into the resulting solution. A base is a substance that releases hydroxide ions (OH –) into solution. pH is a measure
of the hydrogen ion concentration in a solution. The pH scale ranges from 0–14. Solutions with a pH lower than 7 are acidic;
solutions with a pH greater than 7 are basic. A pH of 7 is neutral. When an acid reacts with a base, a salt is formed, along with
water.

Matter can be described by its physical properties, which include shape, density, solubility, odor, melting point, boiling point,
and color. Some physical properties, such as density, boiling point, and solubility, are characteristic of a specific substance and
do not depend on the size of the sample. Characteristic properties can be used to identify unknown substances.

Equal volumes of different substances usually have different masses.

Matter can also be described by its chemical properties, which include acidity, basicity, combustibility, and reactivity. A
chemical property indicates whether a substance can undergo a chemical change.
Properties and Changes
Characteristics of properties are determined by the use of the senses and the involvement of matter in
chemical reactions. Characteristics of changes are determined by a change in the appearance of the substance
or the creation of a new substance with new properties.
Define the following
Physical Property:
Chemical Property:
Physical Change:
Physical Change:
Determine if the following properties are physical or chemical.
1. Color
2. Burning
3. Weight
4. Hardness
5. Reactions with acid
6. Boiling point
7. Density
8. Rusting
Determine if the following changes are physical or chemical.
1. Sharpening a pencil
2. Evaporating water
3. Rusting steel wool
4. Mixing sand and water
5. Burning a pencil
6. Freezing water
7. Spray painting a car
8. Melting ice cream
9. Mixing acid and sugar
Density
Density is a physical property of an object. It is how tightly packed a substance’s compounds are. It is
calculated by taking the mass of a substance divided by its volume, in gm/cm³ or gm/mL. It does not depend
on how much of the object there is because it is expressed as the amount of mass in one cm³ or mass in one
mL.
An object will float on a liquid if its density is less than the density of the liquid. A liquid will float on top of
another liquid if it doesn’t mix with the other liquid and its density is less than the density of the other liquid.
A gold brick has the dimensions of 10cm X 3cm X 2cm. If the mass of this gold brick is 1158 g, what is the
density?
A liquid has a volume of 30 ml and a mass of 15 g. What is the density?
Layer the three solids and liquids in the diagram.
liquid
1
2
3
density
4.5 g/ml
0.7 g/ml
1.0 g/ml
solid
1
2
3
density
2.1 g/cm³
0.4 g/cm³
0.9 g/cm³
Classification of Matter
MATTER
SUBSTANCE
MIXTURE
2 or more substances not chemically
combined
ELEMENT
Compound
Homogeneous
Heterogeneous
All atoms are
More than one
element chemically
combined.
Looks like one substance.
Doesn’t appear the same
throughout
alike
Determine whether the following are elements, compounds, homogeneous mixtures, or heterogeneous
mixtures. Place the letters in the boxes above.
a. hot chocolate
b. oxygen
c. air in the room
d. Italian salad dressing
e. sugar water
f. Lucky Charms cereal
g. carbon dioxide
h. water
i. N2
j. NaCl
Acids and Bases
Acids release H+ ions when dissolved in water and have a pH of less than 7.
Bases release OH- ions when dissolved in water and have a pH greater than 7.
State whether the following are acids or bases.
a. HCl
b. NaOH
c. Al(OH)3
d. H2CO3
e. KOH
Different substances have pH values of 3. 5. 7, 9, and 11.
a. Which is neither an acid or a base?
b. Which is the strongest acid?
c. Which is the weakest acid?
d. Which is the strongest base?
e. Which is the weakest base?
Organic compounds contain the element carbon (C). Inorganic compounds do not contain carbon. For each of the
compounds below, state if they are organic or inorganic.
a. CO2
b. NaCl
c. H2O
d. CH4
e. C6H12O6
f. NO2
g. H2CO3
h. NaOH
The critical scientific concepts developed in this standard include the following:

Many scientists have contributed to our understanding of atomic structure.

The atom is the basic building block of matter and consists of subatomic particles (proton, neutron, electron, and quark) that
differ in their location, charge, and relative mass. Protons and neutrons are made up of smaller particles called quarks.

Size at the atomic level is measured on the nanoscale.

Scientists use models to help explain the structure of the atom. Their understanding of the structure of the atom continues to
evolve. Two models commonly used are the Bohr and the “electron cloud” (Quantum Mechanics) models. The Bohr model
does not depict the three-dimensional aspect of an atom, and it implies that electrons are in static orbits. The “electron cloud”
model better represents our current understanding of the structure of the atom.
Democritus’ atomic theory: atoms cannot be broken down into smaller pieces.
Dalton's Atomic Theory states that
1. All substances consist of tiny particles - atoms and molecules that is matter has a discrete structure.
2. Atoms and molecules are in continuous motion.
3. There exist forces of interaction between the atoms and molecules.
JJ Thomson’s atomic theory: Thomson discovered the electron
Rutherford atomic theory
1. The atom consists mainly of space.
2. The mass of the atom is concentrated in the nucleus, which is a small core at the center of the atom.
3. The nucleus has positive charges.
4. Electrons move around the nucleus like planets orbiting the sun.
5. The atom is neutral as it has the same number of positive and negatively charged electrons.
Niels Bohr model of the atom is very small, positively charged nucleus which contains proton and neutron
surrounded by negatively charged electrons
The Schrodinger/Heiserburg model is called the "quantum mechanical model" and is the model that we use
today to explain and predict atomic behavior. They e indicates that the electron travel randomly in a region or
space around the nucleus rather than in fixed orbits. Each space has a definite energy level. Energy levels have
sub levels, or orbitals within them.
James Chadwick- proved that the neutron was in the nucleus and with neutral charge.
Electrons: negative charge mass 1/2000 amu
Protons: positive charge mass 1 amu
Neutrons: neutral charge mass 1 amu
quarks make neutrons and protons
Isotopes have the same number of protons and electrons but a different number of neutrons. All
elements have isotopes most are radioactive.
Modern atomic theory:
All matter is made of tiny particles called atoms. Each atom is made of smaller subatomic particles
called protons, electrons, and neutrons.
All atoms of one element cannot be converted into the atoms of another element,
Atoms of one element have the same properties such as mass and size. These properties are different
from the properties of another element.
Atoms of different elements combine in specific proportions to form compounds.
Atomic number is the number of protons
Number of protons = number of electrons
Number of neutrons = atomic mass (no decimals) – atomic number
Complete the table below
The critical scientific concepts developed in this standard include the following:

There are more than 110 known elements. No element with an atomic number greater than 92 is found naturally in measurable
quantities on Earth. The remaining elements are artificially produced in a laboratory setting. Elements combine in many ways to
produce compounds that make up all other substances on Earth.

The periodic table of elements is a tool used to organize information about the elements. Each box in the periodic table contains
information about the structure of an element.

An atom’s identity is directly related to the number of protons in its nucleus. This is the basis for the arrangement of atoms on
the periodic table of elements.

The vertical columns in the table are called groups or families. The horizontal rows are called periods.

Elements in the same column (family) of the periodic table contain the same number of electrons in their outer energy levels.
This gives rise to their similar properties and is the basis of periodicity — the repetitive pattern of properties such as boiling
point across periods on the table.

The periodic table of elements is an arrangement of elements according to atomic number and properties. The information can
be used to predict chemical reactivity. The boxes for all of the elements are arranged in increasing order of atomic number. The
elements have an increasing nonmetallic character as one reads from left to right across the table. Along the stair-step line are
the metalloids, which have properties of both metals and nonmetals.

The nonmetals are located to the right of the stair-step line on the periodic table.

Metals tend to lose electrons in chemical reactions, forming positive ions. Nonmetals tend to gain electrons in chemical
reactions, forming negative ions.

Gaining or losing electrons makes an atom an ion.

Gaining or losing neutrons makes an atom an isotope. However, gaining or losing a proton makes an atom into a completely
different element.

Atoms react to form chemically stable substances that are held together by chemical bonds and are represented by chemical
formulas. To become chemically stable, atoms gain, lose, or share electrons.

Compounds are formed when elements react chemically. When a metallic element reacts with a nonmetallic element, their
atoms gain and lose electrons respectively, forming ionic bonds. Generally, when two nonmetals react, atoms share electrons,
forming covalent (molecular) bonds.
Periodic Table Review
Metals are generally shiny, malleable, and hard. Metals are also good conductors of electricity.
Examples of metals are Gold, Silver, Iron, Uranium, and Zinc.
Non-metals do not conduct heat or electricity very well. Non-metals are typically brittle and are not
easily molded into shapes. Example non-metal elements are Hydrogen and Carbon.
Metalloids share characteristics of both metals and non-metals. Metalloids are typically semiconductors, which means that they both insulate and conduct electricity. This semi-conducting
property makes Metalloids very useful as a computer chip material. Examples of metalloid elements
are Silicon and Boron.
Valence electrons are outer shell electrons and determine reactivity of element.
To determine valence electrons group number 1 and 2 and 13 through 18 are 3through 8. Transition metals 1
or 2 and rare earth metals are all 2.
Chemical Formulas
Sub means below…subscript is the number on the bottom right side of the element symbol. No number
means one atom
Large number in from of compound is called a coefficient and it means the number of molecules of the
compound so it is the coefficient times each atom
H2SO4
H=2
S=1
2H 2SO4
H=4
S=2
O=4
O=8
Count the number of each atom.
a. Fe2O3
b. 3CaSO4
c. 5H2O
d. C6H12O6
Bonding
Ionic is between a non-metal and a metal EX NaCl (both are turned into charged ions and opposite charges
attract.)
Covalent bonding is a non-metal and a non-metal Ex H2O (sharing of electrons)
Metallic bonding is a metal to a metal (sharing electrons like a “sea of electrons”)
ID each type of bond
a. CaCl2
b. CO2
c. H2O
d. K2O
e. NaF
f. CH4
g. SO3
h. LiBr
j. MgO
k. HCl
The critical scientific concepts developed in this standard include the following:

Matter can undergo physical and chemical changes. In physical changes, the chemical composition of the substances does not
change. In chemical changes, different substances are formed. Chemical changes are often affected by the surface area/volume
ratio of the materials involved in the change.

The Law of Conservation of Matter (Mass) states that regardless of how substances within a closed system are changed, the
total mass remains the same. The Law of Conservation of Energy states that energy cannot be created or destroyed but only
changed from one form to another.

A chemical equation represents the changes that take place in a chemical reaction. The chemical formulas of the reactants are
written on the left, an arrow indicates a change to new substances, and the chemical formulas of the products are written on the
right. Chemical reactions are classified into two broad types: ones in which energy is released (exothermic) and ones in which
energy is absorbed (endothermic). (The study of synthesis, decomposition, and replacement reactions can be reserved for high
school chemistry.)
Another type of change occurs in nuclear reactions. Nuclear energy is the energy stored in the nucleus of an atom. This energy can
be released by joining nuclei together (fusion) or by splitting nuclei (fission), resulting in the conversion of minute amounts of matter
into energy. In nuclear reactions, a small amount of matter produces a large amount of energy. However, there are potential
negative effects of using nuclear energy, including radioactive nuclear waste storage and disposal
Law of Conservation of mass states that matter can’t ___________________________ or ________________________.
Balancing equations
the number of atoms of the reactants = the number of atoms of the products
This is a combustion reaction between methane and oxygen
=
There is the same number of each atom on each side. Only coefficients can be used to balance the equations
Which of the following equations are balanced? Count the atoms on each side to determine the answer.
A. N2 + 2H2
2NH3
B. PbO2
PbO + O2
C. BaCl2 + Al2O3
D. Pb(NO3)2 + 2NaI
E. FeO4
+ 4H2
BaO + 2AlCl3
PbI + 2NaNO3
Fe +
4H2O
Fission Vs. Fusion Determine which is fusion and which is fission and describe outcome
The critical scientific concepts developed in this standard include the following:

Energy is the ability to do work.

Energy exists in two states. Potential energy is stored energy based on position or chemical composition. Kinetic
energy is energy of motion. Students should know that the amount of potential energy associated with an object
depends on its position. The amount of kinetic energy depends on the mass and velocity of the moving object.

Important forms of energy include radiant, thermal, chemical, electrical, mechanical, and nuclear energy. Visible
light is a form of radiant energy and sound is a form of mechanical energy.

Energy can be transformed from one type to another. In any energy conversion, some of the energy is lost to the
environment as thermal energy.
The Law s Conservation of Energy states that energy states that energy cannot be __________________ or
___________________, it can only change.
There are two types of energy
-potential energy: ___________________________________________________________________________
-kinetic energy: _____________________________________________________________________________
Id each of the following as either as potential or kinetic.
a. rolling rock
b. sitting dog
c. top of waterfall
d. bottom of a roller coaster
e. top of a pendulum
f. bottom of a pendulum
Potential and kinetic energy can be broken down into 7 forms of energy. Give a definition for each form of energy
below.
a. heat energy
b. light energy
c. electrical energy
d. mechanical energy
e. nuclear energy
f. chemical energy
g. sound energy
Use the letters of each of the above forms of energy to identify the following.
____ food
____fire
____ lamp
____ windmill
____battery
____ chain reaction
____ parallel circuit
____ swinging
____ the sun
____ flashlight
____ hot water
____ power in the house
The critical scientific concepts developed in this standard include the following:

Heat and temperature are not the same thing. Heat is the transfer of thermal energy between substances of different temperature.
As thermal energy is added, the temperature of a substance increases.

Temperature is a measure of the average kinetic energy of the molecules of a substance. Increased temperature means greater
average kinetic energy of the molecules in the substance being measured, and most substances expand when heated. The
temperature of absolute zero (–273oC/0 K) is the theoretical point at which molecular motion stops.

Atoms and molecules are perpetually in motion.

The transfer of thermal energy occurs in three ways: by conduction, by convection, and by radiation.

As thermal energy is added to or taken away from a system, the temperature does not always change. There is no change in
temperature during a phase change (freezing, melting, condensing, evaporating, boiling, and vaporizing) as this energy is being
used to make or break bonds between molecules.
Heat energy can be transferred in three ways. Label and describe how the heat is transferred in the pictures below.
Phase Change Diagram
1. What is the state of matter from A to B?_________________________________________
2. What is the state of matter from C to D? ________________________________________
3. What is the state of matter after E?
________________________________________
4. What is the phase change from B to C? __________________________________________
5. What is the phase change from D to E? ___________________________________________
6. What is the heat of fusion? ____________________________________________________
7. What is the heat of vaporization? ________________________________________________
8. How does the temperature change from B to C? _____________________________________
9. How does the temperature change from D to E? _____________________________________
The critical scientific concepts developed in this standard include the following:

Sound is produced by vibrations and is a type of mechanical energy. Sound travels in compression waves and at a speed much
slower than light. It needs a medium (solid, liquid, or gas) in which to travel. In a compression wave, matter vibrates in the
same direction in which the wave travels.

All waves exhibit certain characteristics: wavelength, frequency, and amplitude. As wavelength increases, frequency decreases.

The speed of sound depends on two things: the medium through which the waves travel and the temperature of the medium.

Resonance is the tendency of a system to vibrate at maximum amplitude at certain frequencies.

A compression (longitudinal) wave consists of a repeating pattern of compressions and rarefactions. Wavelength is measured as
the distance from one compression to the next compression or the distance from one rarefaction to the next rarefaction.

Reflection and interference patterns are used in ultrasonic technology, including sonar and medical diagnosis.
Label the waves and their parts: compressions, wavelength, trough, crest, amplitude, transverse wave, longitudinal wave, rest
position, rarefaction
Sound Waves
Use the word bank below ti fill in the reading passage.
Medium
molecules
wavelength
faster
energy
Solids
frequency
travel
close
longitudinal
All waves carry ____________. Sound waves are called ________________________________ waves. They
require a __________________ in order to travel. They travel _____________ in warmer temperatures than
in cold. The waves can _________________ through all states of matter but travel faster through _________
This is because in solids the _________________ are very ___________ together and influence each other. As
the ______________________of the waves increases, the ______________ decreases.
Identify the phenomenon illustrated below and describe what is happening.
The critical scientific concepts developed in this standard include the following:
 Visible light is a form of radiant energy that moves in transverse waves.
 All transverse waves exhibit certain characteristics: wavelength, crest, trough, frequency, and amplitude. As







wavelength increases, frequency decreases. There is an inverse relationship between frequency and wavelength.
Radiant energy travels in straight lines until it strikes an object where it can be reflected, absorbed, or transmitted.
As visible light travels through different media, it undergoes a change in speed that may result in refraction.
Electromagnetic waves are arranged on the electromagnetic spectrum by wavelength. All types of electromagnetic
radiation travel at the speed of light, but differ in wavelength. The electromagnetic spectrum includes gamma rays,
X-rays, ultraviolet, visible light, infrared, and radio and microwaves.
Radio waves are the lowest energy waves and have the longest wavelength and the lowest frequency. Gamma rays
are the highest energy waves and have the shortest wavelength and the highest frequency. Visible light lies in
between and makes up only a small portion of the electromagnetic spectrum.
Plane, concave, and convex mirrors all reflect light. Convex mirrors diverge light and produce a smaller, upright
image. Concave mirrors converge light and produce an upright, magnified image if close and an inverted, smaller
image if far away.
Concave and convex lenses refract light. Convex lenses converge light. Concave lenses diverge light. †
Diffraction is when light waves strike an obstacle and new waves are produced.
Interference takes place when two or more waves overlap and combine as a result of diffraction
Light Waves
Light waves do not need a medium to carry them. There are many types of waves like light waves in the
electromagnetic spectrum.
Light waves travel faster than sound waves, which is why we see lightening before we hear thunder.
Answer the questions about the electromagnetic spectrum shown below.
1. Which wave has the highest frequency?
2. Which wave has the lowest frequency?
3. What is the only part that we can see?
4. What colors is visible light broken into?
5. What happens when you see a green shirt?
Reflection vs. Refraction
Identify each diagram and write a description.
What does the Law of Reflection state?
Lenses and Mirrors
Draw and describe a convex lens and a concave lens.
Draw and describe a convex mirror and a concave mirror.

Several factors affect how much electricity can flow through a system. Resistance is a property of matter that affects the flow of
electricity. Some substances have more resistance than others.

Friction can cause electrons to be transferred from one object to another. These static electrical charges can build up on an
object and be discharged slowly or rapidly. This is often called static electricity.

Electricity is related to magnetism. Magnetic fields can produce electrical current in conductors. Electricity can produce a
magnetic field and cause iron and steel objects to act like magnets.

Electromagnets are temporary magnets that lose their magnetism when the electric current is removed. Both a motor and a
generator have magnets (or electromagnets) and a coil of wire that creates another magnetic field.

A generator is a device that converts mechanical energy into electrical energy. Most of the electrical energy we use comes from
generators. Electric motors convert electrical energy into mechanical energy that is used to do work. Examples of motors
include those in many household appliances, such as blenders and washing machines.

A conductor is a material that transfers an electric current well. An insulator is material that does not transfer an electric current.
A semiconductor is in-between a conductor and an insulator.

The diode is a semiconductor device that acts like a one way valve to control the flow of electricity in electrical circuits. Solar
cells are made of semiconductor diodes that produce direct current (DC) when visible light, infrared light (IR), or ultraviolet
(UV) energy strikes them. Light emitting diodes (LED) emit visible light or infrared radiation when current passes through
them. An example is the transmitter in an infrared TV remote or the lighting course behind the screen in an LED TV or
notebook computer screen.

Transistors are semiconductor devices made from silicon, and other semiconductors. They are used to amplify electrical signals
(in stereos, radios, etc.) or to act like a light switch turning the flow of electricity on and off.
Magnetism and Electricity
Static Electricity: _________________________________________
Correctly label the charges on the diagram.
Current Electricity: Series vs Parallel
Draw and label an example of each circuits.
Answer the following questions about series and parallel circuits.
1. When you add lights to a series circuits, what happens?
2. When you SS lights to a parallel circuit, what happens?
3. What happens in a series circuit when on light goes out?
4. What happens in a parallel circuit when one light goes out?
Complete the circuits in the illustration.
Conductors and Insulators
-Conductors allow for the easy flow of electrons.
-Insulators slow down or stop the flow of electrons.
-Identify each picture below as a conductor or an insulator.
Rubber band
penny
stick
paperclip
nail
Magnetism: Draw the lines of magnetism on the magnets below.
N
S
S
N
-What is an electromagnet?
List 4 ways to increase the strength of an electromagnetic?
N
S
N
S
The critical scientific concepts developed in this standard include the following:

Acceleration is the change in velocity per unit of time. An object moving with constant velocity has no acceleration. A decrease
in velocity is negative acceleration or deceleration. A distance-time graph for acceleration is always a curve. Objects moving
with circular motion are constantly accelerating because direction (and hence velocity) is constantly changing.

Newton’s three laws of motion describe the motion of all common objects.

Mass and weight are not equivalent. Mass is the amount of matter in a given substance. Weight is a measure of the force due to
gravity acting on a mass. Weight is measured in newtons.

A force is a push or pull. Force is measured in newtons. Force can cause objects to move, stop moving, change speed, or change
direction. Speed is the change in position of an object per unit of time. Velocity may have a positive or a negative value
depending on the direction of the change in position, whereas speed always has a positive value and is non-directional.

Work is done when an object is moved through a distance in the direction of the applied force.

A simple machine is a device that makes work easier. Simple machines have different purposes: to change the effort needed
(mechanical advantage), to change the direction or distance through which the force is applied, to change the speed at which the
resistance moves, or a combination of these. Due to friction, the work put into a machine is always greater than the work output.
The ratio of work output to work input is called efficiency.

Mathematical formulas are used to calculate speed, force, work, and power.
MOTION
-Speed, Velocity, and Acceleration
Speed refers to how fast an object is moving. Motion is a change in the position of an object when
compared to a nonmoving reference point. Velocity is the speed of an object and the direction in motion. A
change in velocity is called acceleration. A decreasing velocity is called negative acceleration of deceleration.
The rate of acceleration depends on both the amount of force used and the mass of the object being moved.
Force is a push or a pull that is exerted on an object. When a strong enough force is applied to an
object, the object’s motion changes. If you apply a small force to a massive object (like a car), you will cause a
small amount of acceleration. If you apply a large force to a small object (like a tennis ball), you will cause a
large amount of acceleration. Any object that is moving in a straight line a constant speed is not acceleration.
Answer the following questions about motion.
1. A change in an object’s location is _________________________.
2. A push or pull that is exerted on an object is _________________.
3. __________________ is the speed of an object and its direction of motion.
4. The rate at which velocity changes is ______________________.
Look at the data table and answer the following questions.
1. Which mode of transportation is the fastest?
2. Which mode of transportation is the slowest?
3. What is the distance traveled in all three directions?
Mode
walking
Riding a
bike
Driving a
car
Speed
(KPH)
5
10
Time
minutes
120
60
60
10
Look at the graph and answer the following questions.
1. Which car traveled the fastest?
2. Which car traveled the slowest?
4. What is the average speed? (Average speed = total distance/time)
5. Is the speed of the object constant or not constant? Why?
Mass and Weight
-Mass is the amount of matter in an object. It is measured in grams using a triple beam balance.
-Weight is a measure of the force of gravity on an object. It is measured in newtons and a spring scale.
-You weight will change if you travel to the moon because there is a change in gravity. However, your mass
will remain the same.
-The force of gravity is determined by two things”
-_____________
-_____________
Look at the pictures below and state which position the objects will have the greatest gravitational pull on it.
Identify the pictures as one of Newton’s three laws and state the law and why.
Predict the motion. Read each sentence and predict what will happen according to Newton’s Laws
1. Newton’s Second Law: you hit a ping pong ball and a tennis ball with a tennis racket. Which will travel
farther?
2. Newton’s First Law: If you leave a cookie on a plate and there is no one else in the house, where will the
cooking be in an hour?
3. Newton’s Third Law: If you let the air out of a balloon, what will happen to the balloon?
4. Newton’s Second Law: The horse you are riding on stops quickly. What will happen to you?
Friction
Friction is a
_____________________ that ___________ motion.
Draw the friction arrow in the pictures on the right.
Simple Machines
List the 6 simple machines.
Label all of the simple machines you see in the wheel barrow.
Using Formulas
Speed = distance/time
s= d/t
Force=mass X acceleration
F= ma
Work = force X distance
W=Fd
Power = work/time
P = W/t
A. A train travels a distance of 1,200 kilometer in 20 hours. What is the speed?
B. It takes a caterpillar 15 minutes to crawl 3 meters up a tree. How fast was it crawling?
C. What force gives a 6 kg object an acceleration of 4m/s²?
D. What force gives a 60 kg object an acceleration of 2.2 m/s²?
E. How much work is done when you hold a 50 N box 1.2 metes above the floor?
F. How much work is done when you use 300 N of force to move a box 3 meters?
G. How much power is needed to move a 600 N box 4 meters in 2 seconds?