Aerodynamics: What Causes Lift?

How does an airplane stay aloft when upside down? This media-rich essay from the NOVA Web site offers an explanation based on Newton's third law of motion.

Circular Motion

In this interactive activity featuring videos adapted from the Rutgers PAER Group, observe examples of circular motion. Can you find a common reason why the objects and people presented move in a circle?

Energy Transfer in a Trebuchet

On NOVA, a team of carpenters, timber framers, engineers, and historians recreate a medieval throwing machine called a trebuchet. This adapted video segment explores how understanding energy transfer informs their design.

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Free-Falling and "Weightlessness"

Discover the difference between free-falling and weightlessness in this interactive activity from the NOVA Web site.

Galileo: His Experiments

This interactive activity from the NOVA Web site samples Galileo's experiments with falling objects, projectiles, inclined planes, and pendulums.

Galileo on the Moon

Watch Apollo 15 astronaut David Scott perform Galileo's falling objects experiment on the Moon in this video segment from NASA.

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Galileo's Inclined Plane

How did Galileo figure out the mathematics of falling bodies? This video segment adapted from NOVA examines Galileo's work on motion.

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Galileo's Thought Experiment

How can Earth move through space without our feeling its motion? This video segment adapted from NOVA answers this question by dramatizing one of Galileo's thought experiments.

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Galileo: Timeline of His Life

This illustrated timeline from the NOVA Web site turns back the clock to the late 1500's to relive the dramatic life of one of the world's most renowned scientists.

Getting Airborne and Wing Design

What makes an airplane fly? Discover the connection between Newton's third law of motion and flight in this interactive activity from the NOVA Web site.

Glass Breaking with Sound

In this video adapted from the Encyclopedia of Physics Demonstrations, learn how a glass beaker vibrates at a specific frequency and how resonance can force it to shatter.

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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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Masses and Springs

In this interactive simulation adapted from the University of Colorado's Physics Education Technology project, hang various masses from different springs and see the kinetic, potential, and thermal energy of each spring system. You can even slow time or move your demonstration to another planet.

Momentum

In this interactive activity adapted from Wake Forest University, observe the effect of mass on velocity and momentum in elastic and inelastic collisions.

Newton's Third Law of Motion: Astronauts in Outer Space

In this video segment adapted from NOVA, NASA learns hard lessons from the first American attempt to do work while "walking" in space. The video also explores Newton's third law of motion.

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Projectile Motion

In this interactive simulation adapted from University of Colorado’s Physics Education Technology project, learn about projectile motion by firing various objects from a virtual cannon into the air. Experiment with the settings and try to hit a target.

Sound

This interactive simulation, adapted from the University of Colorado's Physics Education Technology project, illustrates sound waves. Adjust the frequency and amplitude to see and hear how the waves change.

String Theory: Newton's Embarrassing Secret

This video segment from NOVA chronicles Newton's theory of gravity and Einstein's discovery that contradicted it.

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Torque

In this interactive activity adapted from Wake Forest University, observe how rotational force, or torque, is related to the distance between the pivot and the point of the applied force.

Vibration Patterns on a Chladni Plate

In this interactive activity adapted from the University of Southern California, investigate how sound vibrations cause patterns to form in sand on a metal plate.