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Electrical Safety World uses information, experiments,
games, and activities to teach students the principles and practices of
electrical safety. The website is geared for a range of interests and
reading levels and can be used by students in elementary and middle school.
(Non-readers will be able to play the games with adult assistance.)
Part I of this Teacher's Guide describes the contents
of each section of the website. Part II contains questions and activities
teachers can use to focus students' attention on key electrical safety
messages. Part III gives teachers the background they need to set up and
teach the four hands-on experiments on the site.
I. SITE OVERVIEW
The informational areas of the site explain the basic
science of electricity and electrical safety principles with text, pictures,
and experiments. The games simulate common indoor and outdoor electrical
safety situations, giving students a chance to put safety principles into
practice. The activities ask students to apply electrical safety know-how
in their own lives.
Here's what each area contains:
- The Travels of Electricity
(INFORMATIONAL)
What electricity is, where it comes from, and how it travels. Covers
the electric distribution system, conductors, and insulators. Contains
experiments about circuits and conductors/insulators.
- How Electricity Can Hurt You (INFORMATIONAL)
How electricity behaves and how it can hurt people. Covers grounding,
electricity and water, appliance safety, and the effects of electric
shock. Contains experiments about electricity and water, and short circuits.
- Find the Hidden Dangers (GAME)
A game to test students' understanding of how to play it safe around
electricity outdoors. Within busy street scenes, students must identify
electrical hazards involving power lines and electrical equipment.
- Make the Safe Choice (GAME)
A game to test students' awareness about electrical safety inside the
home. The game presents electrical hazards that are relevant to students'
lives and asks students to identify the safest response.
- Shock Blocker (GAME)
Students play against the computer to prevent water from creating a
path for electricity to flow from a power line, electrical outlet or
lightning bolt.
- Tell Me More About Electricity (INFORMATIONAL)
This section is not safety-related but instead provides additional information
for students interested in other aspects of electricity. Covers electricity
basics, electricity generation, pioneers of electrical discovery, electric
vehicles, and energy efficiency/conservation.
- Home Safety Audit (ACTIVITY)
A checklist students can use with parents to inspect their home for
electrical hazards.
- Tell Your Story (ACTIVITY)
Profiles a real-life shock victim who is an Olympic kayaker. Asks students
to interview someone who has had an electric shock, to tell their own
electric shock story, or to report on one from a newspaper article.
Focus is on sharing how the incident occurred and how it could have
been prevented.
- Safety Certificate
This is a checklist of site locations students can use to map their
progress plus an electrical safety pledge. We recommend students print
the certificate before starting the site and have a parent or other
adult sign it after they have visited the eight main areas.
- Glossary
Definitions of electricity-related words found on the site.
- Links to Related Sites
Hot links to related web sites about the science of electricity, electrical
inventions, and electrical safety.
II. QUESTIONS AND ACTIVITIES
These questions and activities review the key safety
principles from the Electrical Safety World website. Here are a few ideas
for how to use them with your class:
- Use as discussion points for verbally reviewing basic
electrical safety information with the whole group.
- Use as a pre- and post-test to assess student understanding
of electrical safety principles before and after visiting Electrical
Safety World. (To use as a written test for older students, cut and
paste the questions into your word processing program, delete the answers,
and print out one sheet for each student.)
- Put students into small groups and assign each group
several questions; ask them to use the website to find the answers.
(Answers to questions 1-12 can be found in The Travels of Electricity;
Questions 13-19 are based on How Electricity Can Hurt You.)
- After all students have completed all sections of
the website, organize the class like a game show: "contestants"
can continue to answer questions until they get one incorrect, at which
point a new contestant takes their place.
Electrical Safety Questions
1. What is electricity a form of? (Energy.)
2. What does electricity travel on to get from the
power plant to people's houses? (Overhead and underground power lines.)
3. What other equipment is involved in getting electricity
to where it can be used by people? (Some or all of the following is
correct: substations, pole-mounted and pad-mounted transformers, service
drops, meter boxes, electrical wiring, appliance cords.)
4. How fast does electricity travel? (At the speed
of light, 186,000 miles per second.)
5. Could you move faster than electricity? (No!)
6. List some good conductors of electricity. (metal,
water)
7. Is the human body a good conductor of electricity?
Why/why not? (Yes, because it is mostly water.)
8. What will happen if electricity travels through
you? (You will be shocked and could be badly hurt or even killed.)
9. List some good insulators. (Special rubber, glass.)
10. Why are insulators important? (They keep electricity
from leaving wires.)
11. What would happen if a power line were to fall
from the power pole to the ground? (It would energize the area around
it with a lot of electricity and people touching the line or coming
near it would be hurt or killed.)
12. If you overload an outlet by plugging in too many
things, what can happen? (Cord insulation can overheat and melt, causing
a shock and fire hazard.)
13. Why are people good conductors of electricity?
(Our bodies are mostly water, and water conducts electricity.)
14. Do you have to be touching the ground directly
to conduct electricity? (No, you could be touching something that is
touching the ground, like a ladder.)
15. Why should you never touch anything electrical
while you have wet hands or while standing in water? (Water conducts
electricity and you could be shocked.)
16. What is the purpose of rubber or plastic insulation
around appliance cords? (It keeps the electricity in the wires and prevents
you from getting a shock.)
17. If a person is shocked, what can happen? (Muscle
spasms, weakness, rapid pulse, severe burns, unconsciousness, or death.)
18. Why can birds sit on power lines without being
shocked? (The birds do not touch the ground or anything in contact with
the ground.)
19. Why could a kite caught in a power line be dangerous
to try to retrieve? (If you touch the kite while you are in contact
with the ground or anything touching the ground, like a ladder, electricity
will travel from the power lines down the kite and into you, and you
will be shocked.)
Activities for Going Further
- Prepare a one-minute presentation for your class on
the basics of how electricity travels from the power plant to appliances
in people's homes.
- Prepare a poster showing electricity going through
a person on its way to the ground. The source of the electricity could
be a power line or an appliance cord.
- Think of three ways you can convince your friends
to be safe around electricity. Share them with the class.
III. EXPERIMENTS
Complete a Circuit
Materials:
Students will need the materials listed (1 D-cell Battery,
1 1.2-volt light bulb, 1 E-10 lightbulb base, two 12-inch pieces of
insulated solid strand 18-22 gauge copper wire with one inch of insulation
removed at each end, masking tape). Bulbs, bases and wire can be purchased
at stores like Radio Shack. Make sure the light bulbs and bases match.
Safety First:
- Students should be supervised by an adult while doing
this experiment.
- A teacher or another adult should be responsible for
stripping insulation from wires.
- Explain to students that electricity can be dangerous
if it is not handled correctly, and emphasize they should never experiment
with the electricity that comes from a wall outlet. It's much more powerful
than the electricity made by small batteries and could seriously injure
or even kill someone.
Objective:
Students will build a circuit and equate it to the
path of electricity that comes from power plants.
Getting it Across:
Have students read the information and follow the
steps on the page.
Make sure they are able to identify the circuit electricity
travels from the battery to the light bulb and back, and the circuit
electricity travels from power plants to homes and back. They should
be able to equate the wires in the experiment with power lines and electrical
wiring in the electric distribution system.
Questions and Answers:
What part of the distribution system is like the wires
in the experiment? Power lines and electrical wiring. What
happens if you only tape one of the wires to the battery? Why? The bulb
does not light. The circuit is not complete unless both wires are taped
to the battery, allowing electricity to flow in a circle.
Go with the Flow
Materials:
Students will need 1 D-cell Battery, 1 1.2-volt light
bulb, 1 E-10 light bulb base, one 12-inch piece and two 4-inch pieces
of insulated solid strand 18-22 gauge copper wire with one inch of insulation
removed at each end, masking tape). Bulbs, bases and wire can be purchased
at stores like Radio Shack. Make sure the light bulbs and bases match.
Students will also need a variety of things they think might conduct
electricity, such as toothpicks, rubber bands, paper clips, plastic,
etc.
Safety First:
- Students should be supervised by an adult while doing
this experiment.
- A teacher or another adult should be responsible for
stripping insulation from wires.
- Explain to students that electricity can be dangerous
if it is not handled correctly, and emphasize they should never experiment
with the electricity that comes from a wall outlet. It's much more powerful
than the electricity made by small batteries and could seriously injure
or even kill someone.
Objective:
Students will learn the difference between conductors
and insulators.
Getting it Across:
1. Have students bring in things they think might
conduct electricity.
2. Have teams read the information and follow the steps on the page.
3. Students should first test their circuit by connecting it without
any trial material.
Questions and Answers:
- Ask teams to share their predictions and results.
Were the results the same? If not, why not? (Answers will vary. Be sure
the experimental setup was not at fault.)
- What conclusions can students draw re: conductors
and insulators? (Answers will vary. Students might generalize that metals
are good conductors or plastic is a good insulator.)
Electricity and Water
Materials:
Students will need the circuits they made for the
Go with the Flow experiment, plus a glass pint or quart jar, 2 nails,
2 alligator clips, salt, and water.
Safety First:
- Students should be supervised by an adult while doing
this experiment.
- A teacher or another adult should be responsible
for stripping insulation from wires.
- Explain to students that anything can conduct electricity
when wet. Remind students that they can mix water and electricity safely
in this experiment because the voltage is so minimal (1.5 V per D cell
battery).
Objective:
Students will demonstrate that water is a conductor
of electricity.
Getting it Across:
Be sure students add plenty of salt to the water.
Then have them predict, experiment, and note their observations. Share
results.
Questions and Answers:
1. Ask students why they think the salt is needed.
(Students will need to add a lot of salt to their water in order for
electric current to flow. The voltage of the battery is so low that
additional particles must be added to make the water MORE conductive.
It is the impurities in water that make it a good conductor. Pure water
will not conduct electricity. However, pure water is only found in the
laboratory. That's why there is so much emphasis on the conductivity
of water as regards electrical safety.)
Ben Franklin Was Lucky!
Materials:
Students will need the circuits they made for the
"Complete a Circuit" experiment, modified as shown in the
illustration (strip a 1-inch section of insulation off the middle of
each wire). Students will also need a 6-inch piece of thicker wire with
one inch of insulation removed at each end.
Safety First:
- Students should be supervised by an adult while doing
this experiment.
- A teacher or another adult should be responsible
for stripping insulation from wires.
- Remind students that they are able to work with these
batteries and wires because the voltage is minimal (1.5 V per D cell
battery). They should never experiment with the electricity that comes
from a wall outlet. It's much more powerful than the electricity made
by small batteries and could seriously injure or even kill someone.
Objective:
Students will be able to describe a short circuit
and compare it to the story about Ben Franklin.
Getting it Across:
1. Have students read the information and follow the
steps on the page.
2. Be sure students understand that they should immediately disconnect
the thick wire and the battery after they observe what happens. The
wires will get hot. This is a clue to why Franklin got shocked.
Questions and Answers:
- Students' predictions and results will vary.
- Why is this called a "short circuit"? (Because
the electricity travels a shorter route than the intended circuit. Electricity
is not able to complete its intended path because the circuit is grounded
somewhere.)
- Why did Ben Franklin get shocked? (His arms functioned
like the thick wire in the experiment. Electricity traveled through
his body instead of through the circuit, and he got shocked.)
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