image credit: Robert Behringer, Duke University

Physics in Action: Whole Grains

In introductory physics you learn how the forces of gravity and friction can change the motion of, for example, a falling rock. But suppose instead of a rock, think about the grains of sand on a beach. The combination of the small mass of each grain and the constant rubbing from the other grains around it make for some interesting physics. To find out more, visit the Physics Central page Granular Materials. Also, check out the surprising images there.

Login to Comment on this Item

Mixing paints and mixing colored lights

Try this Oregon Museum of science and industry simulation, mixing primary colors, to see what happens when you mix red, blue, and green light (and you can change the brightness) or red, blue, and green paint.

Advanced Search

Browse Physics To Go by Topic.

image credit: UVIS, University of Colorado, ESA, and NASA

Saturn's A Ring

This image (hi-res version) shows the region near Saturn's "A" ring, as imaged by NASA's Cassini probe. See Saturn's Rings for a related feature in Physics Central.

You might also enjoy Cassini-Huygens: Mission to Saturn & Titan, the NASA site for this mission.

To see NASA's best images of all the planets in the solar system, and learn about the probes that made them, check out Welcome to the Planets.

Funnel Challenge

An at-home activity that is explained by Bernoulli.