Lesson 2 | Energy Transformations and Work
Name Date Class
Content Vocabulary LESSON 2
Energy Transformations and Work
Directions: Answer each question or respond to each statement on the lines provided. You must include the terms
below in your answers.
energy transformation law of conservation of energy
transform work
1. What does it mean for something to transform?
Change in form.
2. A-What is energy transformation? B-How does a heat lamp provide an example of energy
transformation? C- How does energy transformation relate to a heat lamp keeping an
animal warm?
A-Change of energy from one form to another. B- electric to thermal. C- changing electric to thermal energy
3. How are energy transformations related to the law of conservation of energy?
Total amount of energy does not change, or changes form.
4. Define A-work. B-If you are standing still, C-holding a book, are you doing work? Explain.
A- work is the transfer of energy to move an object in the direction of the force.
B- not, because no force is applied.
C- no, because no force is applied.
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Name Date Class
Content Practice A LESSON 2
Energy Transformations and Work
Directions: On the line before each definition, write the letter of the term that matches it correctly. Some terms
will be used more than once.
B 1. This occurs when energy is converted from one A. law of conservation
form to another. of energy
C 2. This is the transfer of energy that occurs when a B. energy
force makes an object or a particle move. transformation
C 3. This only occurs while the force is acting on the C. work
object.
A 4. This is the idea that energy can be transformed
from one form to another, but it cannot be
created or destroyed.
B 5. When you ride a roller coaster, your gravitational
potential energy is transformed to kinetic energy
and back to gravitational potential energy.
A 6. Even though energy can change forms, the
total amount of energy in the universe does
not change.
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Content Practice B LESSON 2
Energy Transformations and Work
Directions: Circle the term or phrase that correctly completes each sentence.
1. Energy never disappears. It just .
floats changes form
2. When energy is , the form of energy might not change.
transferred stored
3. Humans and other animals transform the energy in plants
into other forms of energy for their life processes.
chemical mechanical
4. When you eat broccoli, your body breaks apart the chemical
in the molecules that make up the broccoli.
energy bonds
5. Forces are .
movements pushes or pulls
6. If you lift a backpack with a force of 20 N, you do work than
if you lift a backpack with a force of 40 N.
less more
7. If you lift a backpack 1 m, you do work than if you lift
it 2 m.
less more
8. is a force between two surfaces that are in contact with
each other.
Energy Friction
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Math Skills LESSON 2
Solve for Work
Work (W) occurs when a force (F) causes an object to move over a distance (d) while the
force is applied to the object. The amount of work is the product of the force that is
applied to the object and the distance that the object moves:
W = Fd
Force is measured in newtons (N), and distance is measured in meters (m). Work is a form
of energy, and it is measured in joules (J). One joule equals one N·m.
A student pushes a chair 4 m across the floor using a constant force of 15 N. How much
work does the student do on the chair?
Step 1 Identify the values given in the problem.
F = 15 N
d=4m
Step 2 Substitute the values into the formulas and solve. Write the correct units.
W=F×d
W = 15 N × 4 m
W = 60 N·m = 60 J
The amount of work done is 60 J.
Practice
1. Rashid lifts a flowerpot 0.8 m off the 3. Mary applies a constant force of 25 N
floor using a constant force of 20 N. as she pushes a desk. In total, she moves
How much work is done on the the desk 12 m. How much work did
flower pot? Mary do?
F= 20N D=0.8m W= ? F=25N D=12m W= ?
W= F × D W= F × D
W= 20 × 0.8 W= 25 × 12
W = 16N W= 300N
2. Lina applies a constant force of 30 N as 4. Bodie lifts his ice skates 0.75 m off the
she pushes a dresser 3 m. How much ground using a constant force of 12 N.
work did Lina do on the dresser? How much work was done?
F= 30N D= 3m W= ? F=12N D=0.75m W= ?
W= F × D W= F × D
W= 30 × 3 W= 12 × 0.75
W= 90 N W= 9 N
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Energy Transformations and Work
Directions: Use your textbook to respond to each statement.
1. Energy can be transformed from one form to another, but it cannot be
created or destroyed.
Describe the energy transformation that occurs as a rock falls off a cliff.
PE CHANGES TO KE
2. Energy can be transformed in a variety of different ways.
Describe two examples of energy transformation that commonly occur.
CHEMICAL TO MECHANICAL
ELECTRIC TO LIGHT
3. Work occurs when a force causes something to move.
Contrast the amount of work done in the following scenarios:
a. Use of a 15-N force to move a box 10 m or use of a 25-N force to move the same box
the same distance
WORK DONE BY 25N IS MORE THAN DONE BY 15N B/C MORE FORCE IS
APPLIED.
b. Use of a 20-N force to move a box 10 m or use of the same amount of force to move
the same box 8 m
MOVING 10 M BY 20N IS MORE FORCE THAN MOVING 8M BY 20N.
c. Moving a box 6 m or holding the same box in the air, but completely still
WORK IS DONE ON A MOVING BOX, WHILE NO WORK IS NOT WHEN ITS NOT
MOVING.
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Name Date Class
Key Concept Builder LESSON 2
Energy Transformations and Work
Key Concept In what ways can energy be transformed?
Directions: Circle the term that correctly completes each sentence.
1. Energy transformation occurs when energy is converted from one
to another.
place form
2. Energy is transferred when it moves from one to another.
object place
3. When you are on a roller coaster at the top of a big hill, you have a lot
of .
gravitational potential energy kinetic energy
4. At the bottom of the hill of a roller coaster, you have a lot of .
gravitational potential energy kinetic energy
5. When a plant carries out photosynthesis, it transforms radiant energy from the
into chemical energy.
atmosphere Sun
6. Eating broccoli chemical energy that your body converts to
energy that your body needs, such as energy for movement, temperature control, and
other life processes.
releases absorbs
7. When electrical energy plants burn fossil fuels, they transform the
from the molecules that were made by plants that lived
millions of years ago.
potential energy chemical energy
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LESSON 2
Key Concept Builder
Energy Transformations and Work
Key Concept How are energy and work related?
Directions: Use the diagram to answer each question or respond to each statement on the lines provided.
1. Describe when work is being done and when it is not being done in the diagram.
*WORK IS DONE WHEN THE DRUM IS MOVING UPWARD.
*WORK IS NOT DONE WHEN THE DRUMMER IS HOLDING THE DRUM.
2. What must occur for work to be done on an object?
MOVEMENT IN THE DIRECTION OF THE FORCE.
3. At which point does the drums’ kinetic energy and gravitational potential energy increase?
WHEN ITS MOVING HIGHER (UPWARD).
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Name Date Class
Key Concept Builder LESSON 2
Energy Transformations and Work
Key Concept How are energy and work related?
Directions: On each line, write the term or phrase that correctly completes each sentence.
1. WORK is the transfer of energy that occurs when a force makes
an object or a particle move.
2. If you are not moving an object, you ARE NOT doing work.
3. If you push a wagon with a force of 35 N, you do MORE work
than if you push a wagon with a force of 10 N.
4. A man lifts a box from the floor 12 m above the floor using a force of 40 N. He is
doing 480N of work.
5. A student pulls his or her trumpet out of its case to begin playing it. The student pulls
the instrument upward 1.75 m with a force of 25 N. He or she does
WORK on the instrument.
6. The direction of friction is in the OPPOSITE direction of the motion.
7. When thermal energy moves from a region of higher temperature to a region of lower
temperature, the energy is called HEAT.
8. Scientists sometimes call this heat WASTED energy, because it is not
easily used to accomplish tasks.
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Lesson Quiz A LESSON 2
Energy Transformations and Work
True or False
Directions: On the line before each statement, write T if the statement is true or F if the statement is false. If the
statement is false, change the underlined word to make it true. Write your changes on the lines provided.
F 1. At the top of a hill, a roller coaster has a lot of kinetic energy.
POTENTIAL
T 2. When electrical energy plants burn coal, they are transforming chemical energy
into electric energy.
T 3. To do work on an object, the object must move in the direction of the force.
F 4. When thermal energy moves from a region of higher temperature to a region
of lower temperature, the energy is called work.
Matching
Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is
used only once.
C 5. released as waste as part of every energy transfer A. work
D 6. Energy cannot be created or destroyed. B. energy transformation
B 7. energy converted to another form C. thermal energy
A 8. when force makes an object move D. law of conservation of
energy
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Lesson Quiz B LESSON 2
Energy Transformations and Work
Short Answer
Directions: Respond to each statement on the lines provided.
1. Define heat in terms of energy movement.
HEAT IS THE TRANSFER OF THERMAL ENERGY FROM HIGHER TO LOWER
TEMPERATURE.
2. Explain why a person who is holding a box in the air and standing still is not
doing work.
BECAUSE NO MOVEMENT.
3. Describe the energy transformation that occurs as a roller coaster rolls down a hill.
PE CHANGES TO KE.
Matching
Directions: On the line before each definition, write the letter of the term that matches it correctly. Not all terms
are used.
C 4. released as waste as part of every energy transfer A. work
B. energy transformation
E 5. Energy cannot be created or destroyed.
C. thermal energy
B 6. energy converted to another form
D. joule
A 7. when force makes an object move
E. law of conservation of
energy
F. photosynthesis
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