PURPOSE: To show that a rubber band contracts when heated.
DESCRIPTION: A torque beam on a pivot is held at one end by a rubber band, as shown in the above left and center photos. A lamp is used to heat the rubber band. A meter stick acts as a marker at the end of the torque beam to indicate the amount of contraction by the rubber band.
EQUIPMENT: Torque beam, rubber band, lamp, meter stick as photographed.
Updated by Jun Qi in 4/5/2000