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Energy Readings

Energy & Energy Transformations Review
Learning Goals – Physical Science 3 A (PS3A)
 List different forms of energy (e.g., thermal, light, chemical, electrical, kinetic, potential
and sound energy).
 Describe ways in which energy is transformed from one form to another and transferred
from one place to another (e.g., chemical to electrical energy in a battery, electrical to
light energy in a bulb).
Energy is the ability to do work. We even say when we are tired and don’t want to work that we
have low energy. Energy comes in many different forms including: heat, light, sound, electrical, kinetic
(motion), potential (energy of position), and chemical. The law of the conservation of energy states that
energy is never created or destroyed. However, energy can be transferred from one object to another and
it can be transformed from one form of energy to another.
Energy Transformations in a Car
Energy transformations can be understood by looking no farther than a car. In the engine, the fuel
(chemical energy) is burned in the cylinder. As the fuel burns, it creates hot gases (heat energy). The gases
expand and press against the piston. Through a combination of rods, shafts, and gears, the piston is
connected to the wheels of the car. The pressure of the
expanding hot gases makes the piston move (kinetic
energy). This causes the wheels to rotate and makes the
car move (kinetic energy).
Not all the energy released when gasoline burns is
transformed to kinetic energy. Most of it becomes heat
energy. That is why the car needs a radiator to prevent it
from overheating. Once the car is moving, the next
important energy transformation comes when the car stops. Friction from the car’s brakes stops the car; in
other words, it reduces the car’s kinetic energy. When the brake pads rub against the brake drums, the
brakes get very hot (kinetic energy is being transformed to heat energy). By the time that a car stops,
almost all the chemical energy stored in the fuel has been converted to heat energy.
1. Gasoline is what form of energy?
2. The moving car has what form of energy?
3. When you step on the brakes what energy transformation takes place?
Putting Wind to Work
The kinetic energy of wind starts from light
energy. The light energy from the sun warms the
earth’s atmosphere unevenly, causing air to move
and create wind. The blades rotate like a propeller
when the wind blows. The blades turn a shaft that
runs into a generator, which transforms kinetic
energy to electrical energy. Electricity then flows
from the generator through the power lines of the
local electric company and carries the energy to the
Putting the wind to work is a good idea for
several reasons. It is environmental-friendly. No
pollution! It is inexpensive. And wind is a
renewable resource meaning that nature will never
run out.
Figure 1.1 The force of the wind turns the blades which
rotates the vertical shaft that is connected to a generator
that transforms the kinetic energy to electrical energy.
1. Write a short summary of how windmills convert kinetic energy of the wind to electrical energy.
2. Discuss at least two reasons why windmills are more environmentally friendly for generating
electricity than methods such as nuclear, or water power (dams).
Directions Draw a line to correctly match the energy transformation description with the correct
1. Kinetic to Heat
2. Electrical to Light
3. Kinetic to Potential
4. Sound to Electrical
5. Electrical to Heat
Directions Match the item(s) you have been given to the correct energy transfer or transformation
Items: Noisemaker, Pinwheel, Glowstick, and Personal Fan
A. Item: Glowstick
B. Item: Noisemaker
In the glowstick, ______________
In the noisemaker, ______________
energy is transformed to ____________
energy is transformed to _____________
C. Item: Personal Fan
D. Item: Pinwheel
In the battery, _____________energy
In the pinwheel, _______________
is transformed to electrical energy, and
energy is transferred to ______________
in the motor, electrical energy is
transformed to ____________ energy.
Always write answers in complete sentences (Starting a sentence with “because” means it is
probably incomplete.)
Be specific! (Avoid using the word “it” as much as possible).
Using what you learned in about energy describe the energy transfer or transformations
for each of the items below.
1. Clapping Your Hands:
2. Dropping Your Pencil:
3. The Toaster:
4. A Cat Lying in a Sunny Window:
5. Lifting a Book Over Your Head:
6. The Radio:
Now come up with two of your own examples and describe the energy transfer or
transformation involved in each.