Download Let`s Convert Energy

ACTIVITY THIRTEEN
Let’s Convert Energy
Point
of Wonder
Have you ever wondered
what forms of energy
surround us each day?
Background
Standard III.4
Energy Forms
and Conversions
Energy can be converted from one form
to another.
Objective
The students will be introduced to
the different forms of energy and
how energy can change from one
form to another.
Instructional Information
and Connections
Time: 60 minutes
Curriculum Focus:
language arts, science
Skills/Processes:
conclude, discuss, draw, experiment, observe
Energy is all around us, all of the time. It may, however, be known
by different names depending on its source. Light, whether it
comes from the sun or a light bulb, is radiant energy. Gravitational
energy is the energy an object has due to its position above the
ground. Food and fuel contain chemical energy, while hot objects
contain thermal energy. A machine with moving parts or a moving
fluid has mechanical energy. Charged objects are filled with electrical energy, and radioactive elements such as uranium contain
nuclear energy.
Another important concept of energy is that it may change forms,
or transform. An electric toothbrush has chemical energy in the battery, which produces electrical energy, which in turn causes that
tooth-scrubbing motion, mechanical energy for pearly whites.
There are two general types of energy that encompass most of its
forms: potential and kinetic. Potential energy is energy waiting to
happen (gravitational, chemical and nuclear forms are potential);
kinetic is energy in motion (thermal, electrical and mechanical
forms are kinetic). That toothbrush sitting on the counter has the
potential energy to clean your teeth. Once the switch is turned on,
that energy is in motion, or kinetic energy.
Materials / Preparation
Key Vocabulary:
chemical energy, conversion,
electrical energy, gravitational
energy, kinetic energy, mechanical
energy, nuclear energy, potential
energy, radiant energy, thermal
energy, wind energy
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Match and candle
Electric kettle or hot plate and pan
Flashlight and batteries
Shallow box (like a shoe box lid) lined with black plastic, and
covered with plastic wrap that has a hole punched in each end
Adhesive tape to hold plastic wrap in place
Plastic bag and twist ties, or zip lock bags, baking soda, vinegar
Yard (meter) stick or board, balls or other objects that roll
Rock collection and geiger counter (if available)
Draw, Describe, Decide Worksheet for each student
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ENERGY FUNDAMENTALS
Connections (cont.)
World of Work:
nuclear engineer
mechanical engineer
chemical engineer
Learning Activity
1. Set up each experiment to show the different forms of energy
either as a teacher demonstration or a hands-on experiment,
depending on the safety of the materials.
Character Connections:
2. Discuss and list the different forms of energy and give examples (as in the Background information).
creative, inquisitive, open-minded,
reach for potential
3. Do the experiments below and have the students fill out their
Draw, Describe, Decide Worksheet.
Correlation Connections:
As you prepare and implement this
activity, record any state or national
standards that may apply:
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A. Light the match. The mechanical energy of striking produces thermal energy from friction, which results in the
release of chemical energy producing heat and light. Now
light the candle, transferring thermal energy from the
burning match to the wick and wax, releasing their chemical energy as heat (thermal energy) and light (radiant
energy).
B. Using the kettle, heat a small amount of water to boiling.
Have the students observe and document the energy path
from the hot plate’s electrical energy which produces thermal energy, which then transfers to the water and produces mechanical energy, or the motion of the boiling
water.
C. Demonstrate the flashlight without the batteries and again
with the batteries. Help the students understand the energy conversions from the chemical energy of the batteries
to the electrical energy that heats (thermal energy) the
bulb filament and produces light (radiant energy).
D. Place the prepared
shallow box in a sunny
windowsill with one
hole up. Have the students place their hand
over the top hole. What
happens? The sunlight
(radiant energy) is
absorbed by the black
lining and turns to heat
(thermal energy) which
is trapped by the plastic wrap. As the air
heats up and expands,
it is pushed out the top
by cooler, denser air
entering at the bottom.
(Explain to the students
that this is a good illustration of how wind is
produced by heating of
the earth’s surface.)
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ENERGY FUNDAMENTALS
E. In one corner of a plastic bag, place a spoonful of baking soda and seal off the corner with a
twist tie. Then pour in about 50 mL (about 1/4 cup) vinegar, squeeze the air out and seal the
bag (use another twist tie or a zip lock bag). Take off the first tie and let the two chemicals mix.
Note the signs of a chemical reaction: production of gas bubbles which inflate the bag and a
change in temperature drop inside the bag. This reaction takes in heat and releases chemical
energy.
F.
Elevate one end of a board or meter stick. Roll a ball down the board to demonstrate gravitational energy. Let the students experiment with the mechanical energy applied at the top, the
weight of rolling objects, and the ability to knock over objects at the bottom. The concept would
be fun to illustrate using a playground slide or teeter-totter.
G. If you have access to a geiger counter, test a rock collection, wrist watches (some contain radium), and a few other materials to demonstrate nuclear energy radiating from these materials.
4. Discuss the observations and the results of the Draw, Describe, Decide Worksheet.
Check for Understanding
Have the students draw an energy conversion including three forms of energy (e.g., electrical energy
used to produce thermal energy, which toasts a piece of bread, giving chemical energy to the consumer—the person who eats the toast).
Have students record two or three examples of each form of energy they have seen or used during their
experiments today.
To Know and Do More
Make a list of examples of potential (energy waiting to happen) and kinetic (energy in motion) energy.
Potential
Kinetic
a truck at a stoplight
water behind a dam
a skier standing still
a piece of wood
a
a
a
a
truck moving down the road
running river
skier racing down the hill
piece of wood burning
Have a three-minute challenge to see who can come up with the most examples.
Have students research the terms chemical reaction, exothermic and endothermic. Which experiments
contained chemical reactions? (burning the match, using the battery, and the baking soda and vinegar)
Which were endothermic? (baking soda and vinegar) Exothermic? (burning, reaction inside the battery)
Career Awareness Activity
Have students research the career of a physicist. What education is required? What is their general area
of interest? What is the pay scale? Can a physicist specialize in a particular field or area?
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ENERGY FUNDAMENTALS
Draw, Describe, Decide Worksheet
Fill in each column as the experiments or demonstrations are completed.
Sketch the experiment
Describe what happened
Decide the energy forms involved
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A.
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B.
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C.
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D.
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E.
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F.
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G.
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National Energy Foundation