Physics -- Sounds Too Cool To Be True?
Sound waves are produced by a vibrating body. The vibrating object moves in one direction and compresses the air directly in front of it. As the vibrating object moves in the opposite direction, the pressure on the air is lessened so that an expansion, or rarefaction, of air molecules occurs. One compression and one rarefaction make up one longitudinal wave.
So, how can you put the energy of sound waves to good use on a hot summer day? Before you say "garage band," consider this: Dr. Stephen Garrett and his team of brainiacs from Penn State University have teamed up with Ben & Jerry's to produce a sound-powered refrigeration unit for storing ice cream. Now, who wouldn't like the sound of that?








