Content Standard B
— As a
result of the activities in grades K-4, all students should develop
of light, heat, electricity, and magnetism.
Electricity in circuits can produce light, heat, sound, and magnetic
effects. Electrical circuits require a complete loop through which
an electrical current can pass.
— As a
result of their activities in grades 5–8,
all students should develop an understanding of transfer of energy.
Electrical circuits provide a means of transferring electrical energy
when heat, light, sound, and chemical changes are produced.
— As a
result of their activities in grades 9-12, all students should
develop an understanding of motions and forces; interactions of
energy and matter.
Electricity and magnetism are two aspects of a single electromagnetic
force. Moving electric charges produce magnetic forces, and moving
magnets produce electric forces. These effects help students to understand
electric motors and generators.
waves result when a charged object is accelerated or decelerated.
Electromagnetic waves include radio waves (the longest wavelength),
microwaves, infrared radiation (radiant heat), visible light, ultraviolet
radiation, x-rays, and gamma rays. The energy of electromagnetic
waves is carried in packets whose magnitude is inversely proportional
to the wavelength.
Click to view larger image
Benjamin Franklin's experiment with the kite "..when
the string was thoroughly wet, abundance of electricity was procured..." In: "The
Thunder-storm" by Charles Thomlinson, F.R.S., 1877, p. 30.
NOAA Photo Library
"Whoever wishes to get
a true appreciation of the greatness of our age should study the
history of electrical
development." — Nikola Tesla, 1915
Charge up your classroom with cool experiments, awesome demonstrations,
and noteworthy historical information about electricity. Learn about
people who made major scientific contributions that opened up new
frontiers leading to household lighting, the long-distance transmission
of power, and electronic devices that made life easier. Visit these
Web sites for background information, illustrations, explanations,
lessons, and insight into the world of electricity.
His Electric Kite
How did Franklin's experiment with the kite work? Why did Franklin
remain unscathed while holding the string? Why was he shocked when
he touched the key? Answers to these questions plus a wealth of historical
information can be uncovered at this site.
Inventing Entertainment: The Motion Pictures and Sound Recordings
of Thomas Edison
This American Memory collection from The Library of Congress features
341 motion pictures, 81 disc sound recordings, and other related
materials, such as photographs and original magazine articles. In
addition, there is a timeline and biography about Thomas Edison.
Tesla: Master of Lightning
Edison is well known for his many inventions, Franklin
for his kite experiment, but who is Nikola Tesla and what scientific
did he make during his lifetime? Nikola Tesla was considered a genius
in the area of low-frequency electrical power generation and transmission
at the turn of the 20th century. Some of his key inventions were
alternating current, the Tesla coil, and remote control. Tesla also
conducted experiments on transmitting electrical power from one point
to another without wires. Unfortunately, he was decades ahead of
the wireless technology, and the project was abandoned. George Westinghouse
purchased Tesla's patents, but it would not be until the 1930s that
another attempt was made to transmit power without wires in the confines
of the Westinghouse Laboratory. [See the sidebar "An Early Attempt
at Wireless Transmission."]
WORLD OF ELECTRICITY
Ippex Online: Electricity and Magnetism
Students will enjoy this virtual learning module on electricity
and magnetism. Concepts covered include charged particles, electric
current, resistance, voltage, and circuits. Through a series interactive
visualizations, students will learn about static charges, how to
construct a circuit, and the relationship between magnetism and electricity.
This project originated in 1996 at the Princeton University Plasma
Physics Laboratory as part of a National Science Foundation grant,
administered by the Center for Improved Engineering and Science Education
(CIESE) at the Stevens Institute of Technology.
Theater of Electricity
Why is it safe to be in a car during a lightning storm? (The answer
is not that it has rubber tires.) How did Benjamin Franklin conduct
his kite experiment? What are Tesla coils? Learn fascinating facts
about electricity at the Boston Museum of Science site, demonstrated
by the Van De Graaf generator. Robert Van De Graaf built the generator
in 1931 to conduct early atom smashing and high-energy X-ray experiments.
The Massachusetts Institute of Technology donated the generator to
the museum in the early 1950s. Today it is used to educate the public
and school children about electricity and lightning.
What Is Electricity?
The first question you
may ask is what is electricity? Electricity has several different
and contradictory meanings. According to this
article written by Bill Beatty, electrical engineer, there is no
such thing as "electricity." Instead, there are names for
all the separate phenomena associated with the term. Read this thought-provoking
essay and see what you think.
Four sections target different audiences. In Louie's Space, grades
1-4 are given a tour through the science, history, and safety of
electricity. New Frontiers is designed for grades 5-8 and covers
safety, conservation, and careers. Mind Power is well suited for
teenagers in grades 8-12, with loads of information for reports,
including brief biographies and illustrations of inventors. Rounding
out the site is the Teachers Lounge, which contains experiments,
a glossary, and links to other sites.
Electrical Safety World
Electrical Safety World usesvideos to answe rquestions about elevtricity and be safe.
- Electrical Safety
- Electrical Safety World Videos for Kidss.
Check out this PBS site for an excellent visual demonstration of
the differences between direct current and alternating current. The
scientific principles behind batteries, copper wire, and light bulbs
are also described.
Snacks About Electricity
All sorts of teacher-tested experiments are presented in the Exploratorium's
Snackbook series. In the electricity section, discover how a pinball
machine works, make a simple motor, start an electric flea circus,
and investigate electric phenomena.
Sparks of Light
Create a lab in your classroom. Decide on a list of experiments.
Organize your students into groups of scientists and let them decide
which experiment to try. Design how you want to conduct the experiments.
You may want to begin with a hypothesis or determine probability.
Have your students keep a journal or log. Use a spreadsheet to chart
and evaluate the results. Watch as your scientists light up with
awe over the wonders of electricity.
This is a great way to introduce electricity to students or to evaluate
their knowledge. See how many ways your students can light a bulb
with the following materials.
wire, 6 inches long; or a 1/2-inch-wide, 6-inch-long piece
of aluminum foil
* D-cell battery
* Flashlight bulb
* Tape (optional)
1. Strip the ends of the wire so 3/4-inch to 1 inch is showing.
2. Experiment with connecting the wire/aluminum foil, battery, and
light bulb until the bulb lights up.
3. Sketch your designs and mark what worked and didn't work.
What differences are there between the two ends of the battery?
Where should the wires be placed? Why?
What happened to the battery when both ends of the wire/aluminum
foil were connected to it? Why?
What were you creating through this experiment?
What kind of current is being used?
Caution: The battery becomes hot when doing this experiment.
In this activity you will measure the voltage of
a "fruit battery*" using
An Early Attempt at Wireless
was the basis for a demonstration of power transmission without wires
at the Westinghouse exhibit at the Chicago World's Fair of 1933-1934.
The light shown
in the picture needs no current. It lights merely by reason of
its presence in an ultra-high-frequency field. The field is produced
by a standing wave oscillator, which sends out from the antenna
overhead 15,000 watts of power as ultra-short radio waves (known
as microwaves today).
power lights all lamp bulbs within 40 feet, cooks food in a matter
of seconds, and raises body temperature 1 degree per minute—all
due to the electro-magnetic field. In the picture, H.V. Noble,
Westinghouse research engineer, hurriedly explains the phenomenon
to Evelyn Tray (left) and Vera Goga, because, after a few more
minutes in the field's influence, they too will feel "lit."