Name: _________________________________________
Period
1
2
3
4
5
6
7
8
Date: ___________________
Physical Science
Notes: Potential and Kinetic Energy
Directions: Read and highlight the following information. Be sure to answer the questions
on the side as you are reading.
The many forms of energy
1. What did you think
People frequently use the word “energy.” You might hear people
energy was before
use phrases such as:
reading the first
section of these
“I was going to do it, but I didn’t have the energy.”
notes? (be honest)
“I had so much energy yesterday; I was able to accomplish so
much.”
What exactly is energy? Energy is defined as the ability to do work,
so it makes sense that people often talk about energy in terms of
how much work they were able to get done in a particular time.
There are two major classifications for the various forms of energy
that we know about. The two categories are potential and kinetic
energy.
2. Use the word
energy correctly in a
sentence:
3. Interpret the
cartoon to the left in
the space below:
Figure 1 – Cartoon about the dangers of smoking and
shoveling snow. It requires a great deal of energy to shovel
snow. Health experts report a tremendous increase in the
risk of a heart attack during snow shoveling, especially for
smokers.
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Potential Energy:
4. Provide an
example of each
Potential energy is defined as stored energy that results from the
type of potential
current position or arrangement of matter. For example, a rock
energy. Draw and
that is held above the ground is said to have gravitational potential label your example
energy, or potential energy due to the force of gravity. If the rock is with a few words.
released, it will fall and work will be done. Work, a concept that will
be explored in the next unit, is when an object moves a distance as
a result of a force being applied to it. If nothing moves, then work is Gravitational:
not being done.
There are many forms of potential energy. Table 1 below illustrates
and describes many of these forms of potential energy. Remember,
when talking about potential energy we are always taking about
stored energy.
Table 1: Forms of Potential Energy
Potential energy type
Illustrations/Examples
Chemical:
Chemical potential energy
(energy stored in chemical
bonds)
Mechanical:
Mechanical/Elastic potential
energy (energy stored in
devices that can be compressed
or stretched and then released)
Nuclear:
Nuclear potential energy
(energy stored in the bonds
that hold the nucleus together)
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Gravitational potential energy
(energy stored as a result of
objects raised off the ground
or place at the top of a hill)
*Note: there is no one specific formula to calculate potential
energy because there are many forms of potential energy and
therefore a list of formulas that could be used depending on the
type.
Kinetic Energy:
Kinetic energy is defined as the energy that an object or particle of
matter has because of its motion. In simple terms, kinetic energy is
the energy of motion. Kinetic energy can be quantified or measured
using the following equation.
Sample problem:
m = mass
If an object that weighs 1 kg is
moving at 1 m/s, it is said to
v = velocity
have 1 Joule of energy.
Kinetic energy is measure in
K = energy
Joules (J)
There are many forms of kinetic energy. Table 2 below illustrates
and describes many of these forms of kinetic energy. Remember,
when talking about kinetic energy we are always taking about
energy in motion.
Table 2: Kinetic energy forms
Kinetic energy type
Illustration
5. Define kinetic
energy in your own
words in the space
below:
6. Write the formula
for kinetic energy in
the space below:
7. What is the unit of
measurement of
energy?
8. Provide an
example of each
type of kinetic
energy. Draw and
label your example
with a few words.
Electrical:
Electrical kinetic energy
(energy of moving electrons)
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Radiant:
Radiant kinetic energy (light, xrays, gamma rays, radio waves)
Thermal (heat) kinetic energy
(energy of vibrating molecules)
Motion energy (moving
objects)
Sound energy (vibrating
material producing sound)
Thermal:
no picture is provided for this
type of energy; think about
anything moving from objects
as small as electrons to objects
as large as a planet
Motion:
sound waves
travel at 767
miles per hour
in dry air at 20
degrees celsius
Sound:
Renewable and Non-renewable energy:
Another way to classify energy aside from calling it either potential
or kinetic is the concept of renewable and non-renewable energy.
As human populations and energy needs continue to grow at
exponential rates, this is a major concern for societies and
governments around the world. We will hold an in-class debate
about the merits of pursuing alternative (renewable) energy
sources.
Non-renewable energy comes from energy sources that are finite,
or have a limited supply. The Earth only has a certain amount of oil,
coal, natural gas, and radioactive material. Although many
scientists and politicians make bold (and possibly inaccurate)
statements about when these resources will run out, it is a fact that
they are limited in supply. Therefore, they could be completely
9. Define nonrenewable energy in
your own words:
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consumed and exhausted as an energy resource. Aside from that,
these sources of energy are often accompanied by high levels of
pollution to the atmosphere, hydrosphere, and lithosphere and are
likely linked to human and other species health problems.
10. Define renewable
energy in your own
words:
*Note: it is possible that in the future, new methods of creating
energy using radioactivity will be developed. Currently, we have
classified nuclear energy as a non-renewable energy source
because of the way that nuclear energy is created – using Uranium. 11. What is a possible
We have a limited supply of usable Uranium to create electricity
advantage to using
with nuclear processes and it is therefore non-renewable.
renewable sources of
energy instead of
Renewable energy comes from sources that are generally thought
non-renewable
of as infinite (never-ending). Will the wind ever stop blowing, the
sources?
Sun ever stop shining, or water ever stop flowing downhill? It is
extremely unlikely that in our lifetimes or many lifetimes to come
that any of those things will stop; they all can be used as sources of
energy. In addition, there is generally less of an environmental
impact associated with acquiring, developing, and using these
renewable sources of energy. Pollution can greatly be reduced with
renewable energy sources.
Table 3: Renewable vs. Non-renewable energy
12. List all three
forms (solid, liquid,
Renewable energy
Non-renewable energy
gas) of
Coal – black/brown solid
Solar – the Sun’s energy can be
hydrocarbons, which
remains of plant matter that
used in several ways to
are also called fossil
can be burned as a fuel to
generate electricity
fuels:
generate electricity
Oil (petroleum) – brown/black
Wind – wind can be used to
liquefied remains of plant
turn a turbine that can
matter that can be burned as
generate electricity
fuel to generate electricity
Natural gas – a mixture of
Water (hydroelectric) – moving
gaseous hydrocarbons that can 13. List three forms
water can be used to generate
of renewable energy:
be burned as fuel to generate
electricity
electricity
Geothermal – heat from
Nuclear power – fission
magma inside the Earth can be reactions (splitting atoms) are
used to generate electricity
used to generate electricity
Biomass – plant and animal
matter can be used as a fuel
(burned) to generate electricity
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Energy conservation
In terms of energy, conservation can be defined as the careful and
sensible usage of energy so that we can prevent and slow the
depletion of that resource. Depletion means disappearing in the
previous sentence; it is important that our society has enough
energy to suit its needs. Energy conservation can take many forms
in our daily lives. The table below some examples of energy
conservation.
Table 4: Energy conservation
Turn off lights and heat when
In the home
not at home or not in certain
areas of the home
Use cars/trucks that get better
In the car
gas mileage
Go green! Use electronic
At work
communication instead of
paper.
Efficiency is a relevant concept in a discussion of conservation.
Energy efficiency can be thought of as a comparison (ratio) of the
energy input to a machine or system with the energy output. A
system that has a higher energy input than output can be called
“inefficient.” The more energy output a machine/system has
relative to its energy input, the more efficient it can be said to be.
Efficient systems will help humans conserve energy and therefore
resources.
14. Define energy
conservation in your
own words and
come up with three
strategies (not in the
notes) that you can
do to conserve
energy in your daily
life:
Conservation:
1.
2.
3.
15. Pick one of your
daily activities
(studying, exercising,
sports, reading,
chores, etc…) and
describe how you
can increase your
efficiency:
Activity:
Figure 2 – energy efficient lightbulb. This fluorescent bulb
uses less electricity to provide light than the traditional
incandescent bulb (old fashioned bulb). It is more
efficient because there is less energy input for a similar
output.
Strategy:
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Vocabulary – Only Bold Words Are Required
Term
Definition
Energy
Potential energy
Gravitational
potential energy
Work
Chemical
potential energy
Mechanical/Elastic
potential energy
Nuclear potential
energy
Electrical kinetic
energy
Radiant kinetic
energy
Thermal (heat)
kinetic energy
Motion energy
(moving objects)
Sound energy
Non-renewable
energy
Renewable
energy
Conservation
Efficiency
Wrap – Up - Answers to the following questions can be found in your notes.
1. Draw a picture below that involves at least four energy transformations. The picture
must include labels of each energy type, arrows to indicate the transformations, and at
least two sources of renewable energy.
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2. Write a complete sentence to describe at least two benefits of using renewable energy
over non-renewable energy sources:
____________________________________________________________________________
____________________________________________________________________________
The diagram below represents several forms of electromagnetic energy.
3. Which feature best distinguishes one form of electromagnetic energy from another?
(1) color
(2) wavelength
(3) surface temperature
(4) distance traveled
4. Use the table to fill in the grid below and answer the questions that follow.
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a. Use the grid above to construct a line graph from the data in the table. Follow the steps
below. Use Xs to plot the data for time and temperature and draw a solid line that
connects the Xs.
b. Provide an appropriate title for the graph: _______________________________________
c. According to your graph, what would the temperature of the substance be at 23
minutes? _______ °C
d. What is the independent (manipulated) variable in this experiment? _________________
e. What is the dependent (responding) variable in this experiment? ____________________
Base your answers to questions 5 and 6 on the information below and on your knowledge
of science. The diagram shows a person observing a thunderstorm located several
kilometers away. The person hears the thunder several seconds after seeing the lightning.
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5. Identify a form of energy, other than light and sound that is often present during a
thunderstorm. ____________________________________
6. Explain how sound travels through the air to the observer.
____________________________________________________________________________
____________________________________________________________________________
Base your answers to questions 7 and 8 on the diagram below and on your knowledge of
science. The diagram shows two students ready to dive into a pool.
7. Explain why student B has more potential
energy than student A.
________________________________________
________________________________________
8. Student A dives from the board into the
water. Explain why student A’s kinetic energy
decreases as the student enters the water.
________________________________________
________________________________________
________________________________________
________________________________________
________________________________________
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Enrichment: The enrichment questions are an extension of your learning. These
questions are not required but strongly recommended to help reinforce your learning. The
questions that follow are taken from former High School Chemistry Exams that are about
energy and energy related concepts. If answered correctly, extra credit (up to three
points) will be awarded to you.
1. Given the balanced equation representing a reaction:
H+(aq) + OH–(aq)
H2O(_) + energy
In this reaction there is conservation of
(1) mass, only
(2) mass and charge, only
(3) charge and energy, only
(4) charge, energy, and mass
2. Which process increases the potential energy of the particles of a sample?
(1) condensation
(2) deposition
(3) solidification
(4) vaporization
3. In which sample is the average kinetic energy of the particles greatest?
(1) 10 mL of HCl(aq) at 25°C
(2) 15 mL of HCl(aq) at 20.°C
(3) 10 mL of H2O(_) at 35°C
(4) 15 mL of H2O(_) at 30.°C
4. Systems in nature tend to undergo changes toward
(1) lower energy and less disorder
(2) lower energy and more disorder
(3) higher energy and less disorder
(4) higher energy and more disorder
Given the balanced equation representing a reaction:
Cu + S
CuS + energy
5. Which statement explains why the energy term is written to the right of the arrow?
(1) The compound CuS is composed of two metals.
(2) The compound CuS is composed of two nonmetals.
(3) Energy is absorbed as the bonds in CuS form.
(4) Energy is released as the bonds in CuS form.
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Teacher Answer Key:
Wrap-up questions
1. Any number of drawings are acceptable; teacher should u se best judgment to
grade.
2. Renewable energy is cleaner and has less of an environmental impact; renewable
energy has sources that are not finite or limited.
3. 2
4. A – teacher needs to construct the graph him/herself; b – Time vs. temperature; c –
interpret teacher created graph for answer; d – time; e – temperature.
5. Electricity or heat.
6. Sound travels in waves through the air as vibrations.
7. Student A is located at a higher position above the water.
8. The water will create friction and slow down the student, effectively reducing the
student’s kinetic energy.
Enrichment questions
1.
2.
3.
4.
5.
4
4
4
2
4
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