AC / DC: What's the Difference?

This animated essay from the American Experience Web site explains the difference between alternating and direct electric current and offers in-depth explanations about the role played by a battery, light bulb, wire, and generator.

Bandwidth and Data Conversion

This interactive activity adapted from the Wisconsin Online Resource Center describes the factors that affect the speed of data transfer in computer networking systems and some of the techniques used to increase the data capacity of these systems.

Beyond Einstein

NASA scientists describe some of the ways current science is addressing several of Einstein's fundamental questions and theories in this video adapted from NASA.

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Bringing Down the Bolt

Learn about how lightening strikes in this video segment from Science Friday.

Designing Electric Circuits: Door Alarm

In this video segment adapted from ZOOM, cast members design and build door alarms using a variety of materials, including aluminum foil, batteries, and buzzers.

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Designing Electric Circuits: Steadiness Tester

In this video segment adapted from ZOOM, cast members discover that metal is a good conductor of electricity as they play the steadiness tester game.

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Designing Future Cities: Alternative Energy

In this video segment adapted from ZOOM, visit a class as they design a city of the future that will use solar, wind, and water power to fuel its economy.

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Dust-Proofing a Mars Rover

Enter the lab of NASA scientist Dr. Carlos Calle to see how systems are being developed to keep planetary rover solar panels dust-free, in this video from NASA EDGE.

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Electric Charges Interact

Experiment with electric charges to find out how they interact in this interactive activity adapted from NASA.

Electric Circuits

Students model, build, and draw diagrams of electric circuits and test the conductivity of a variety of materials.

Electric Girl

Anna loves electricity. Watch her construct a homemade flashlight and show off her new, electrifying hairdo in this video segment from ZOOM.

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The Electromagnetic Spectrum: FRONTLINE

This video segment adapted from FRONTLINE introduces the electromagnetic spectrum and explains how the various types of electromagnetic waves are distinguished by the amount of energy each wave carries.

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The Electromagnetic Spectrum: NASA

From radio waves to gamma rays, this video segment from NASA introduces the seven categories of the electromagnetic spectrum and how each type of radiation is part of our everyday lives.

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Electrophoresis and Gel Analysis

In this animation produced by WGBH and Digizyme, Inc., see how molecules of DNA are separated using gel electrophoresis, and how this process enables scientists to compare the molecular variations of two or more DNA samples.

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Energy Sources

This video segment illustrates a variety of energy sources used to generate electricity, some of which are in use and some of which are under exploration.

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Experimenting with a Lemon Battery

Can a fresh lemon power a digital clock? In this video segment adapted from ZOOM, the cast shows you how this can be done and, in the process, discover how kids can be a part of an electric circuit.

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Exploring Conductivity: Kid Circuits

In this video segment adapted from ZOOM, cast members join hands and become electron conductors to complete an electric circuit.

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Generating Electrical Voltage

This interactive resource adapted from the Wisconsin Online Resource Center illustrates how electrical voltage is generated through a process called magnetic induction and describes some of the factors that affect the magnitude of the voltage produced.

Generation of Alternating Current

This interactive resource adapted from the Wisconsin Online Resource Center illustrates the parts of an electrical generator and shows how they function to produce alternating current.

Hoover Dam and Hydroelectric Power

How does a dam generate electricity and what are the environmental impacts of operating these mammoth structures? Find out in this video segment adapted from Building Big.

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Infrared Energy

Explore infrared energy and how NASA detects it to study our Earth's systems more completely in this video adapted from NASA.

Infrared Gallery

How would your world look if you saw heat instead of light? In this interactive resource produced for Teachers' Domain, see what familiar objects look like through an infrared camera and watch infrared videos of geysers, mudpots, and hot springs.

Infrared: More Than Your Eyes Can See

In this video segment adapted from NASA, astronomer Michelle Thaller introduces the world of infrared light and demonstrates how infrared cameras allow us to see more than what the naked eye can perceive.

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Inside a Solar Cell

This interactive activity adapted from NOVA Online features animations that illustrate the components of a typical photovoltaic cell and how it converts solar energy into electricity.

Inspector Detector Challenge

In this video from Design Squad Nation, kids design and build magnetic-field detectors and use them to find hidden magnets. They also learn how NASA uses magnetometers to learn what is going on inside a planet or moon.

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Inverse Square Law

This animation from KET's distance learning physics course demonstrates the mathematical formula for a scientific law as it applies to light.

Invisible Force Challenge

In this video from Design Squad Nation, kids design and build systems that use magnets to control the speed and direction of a rolling ball. They also learn how NASA uses gravity to direct a spacecraft.

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Kid Inventor: The Couch Protector

Want to keep your dog off the couch? In this video segment from ZOOM, Jason demonstrates his invention that does just that: a couch protector.

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Let’s Make Some Static!

In this lesson, based on the Science Friday video Bringing Down the Bolt, students will generate static electricity by rubbing or “charging” a balloon.

Lightning!

This video segment adapted from NOVA explains the mysterious force of lightning.

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Lightning Hunters

Find out how scientists and engineers use rockets to attract lightning in this video segment adapted from NOVA.

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Making Waves with the Electromagnetic Spectrum

Students explore various types of electromagnetc waves to better understand the electromagnetic spectrum.

Mapping Magnetic Fields

This video adapted from NASA explains how a magnetometer determines magnetic fields around planets.

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Meet Carrie Anderson: Taking on Titan

In this video from NASA, astronomer Carrie Anderson studies Saturn's moon, Titan, using data transmitted from the Cassini space probe.

A New Theory of Lightning

In this video segment adapted from NOVA scienceNOW, follow scientists as they test a new theory suggesting that lightning here on Earth is triggered by cosmic rays from far-away dying stars.

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Ohm's Law

In this interactive simulation of Ohm’s law, adapted from the University of Colorado's Physics Education Technology project, adjust the voltage and resistance in a circuit, and observe how this affects the flow of current.

Radio Waves & Electromagnetic Fields

In this interactive simulation adapted from the University of Colorado's Physics Education Technology project, explore how a radio transmitter broadcasts electromagnetic radiation.

Smart Power Grid

This video segment adapted from NOVA scienceNOW provides an overview of the existing United States power grid, and envisions a "smart" power grid that would prevent problems, such as blackouts, and reduce energy waste and pollution.

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Static Electricity: Snap, Crackle, Jump

In this video segment adapted from ZOOM, see static electricity make breakfast cereal jump and hair stand on end.

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String Theory: A New Picture of Gravity

This video segment from NOVA describes the general theory of relativity and the theory of electromagnetism.

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String Theory: A Strange New World

This video segment from NOVA chronicles Einstein's quest to unify the forces of electromagnetism and gravity.

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Testing for Static Electricity

In this video segment adapted from ZOOM, cast members show you how to make your very own electroscope. You can use it to find out if an object is electrically charged.

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Tour the Electromagnetic Spectrum

Take NOVA's interactive tour of the electromagnetic spectrum and find out why your eyes are like antennae for a narrow band of electromagnetic radiation.

Volcanoes in the Infrared

In this video adapted from KUAC-TV and the Geophysical Institute at the University of Alaska, Fairbanks, satellite imagery and infrared cameras are used to study and predict eruptions of volcanoes in the Aleutian Islands, Alaska.

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WMAP: "Baby Picture" of the Universe

View the Wilkinson Microwave Anisotropy Probe (WMAP) image from NASA to see the first detailed map of the oldest light in the universe, from 379,000 years after the Big Bang, over 13 billion years ago. A second image offers a visual timeline to put the WMAP image in perspective.