Heating a rubber band: negative coefficient of thermal expansion

Heating a Rubber Band: negative coefficient of thermal expansion. A rubber band is connected between a table stand and a force transducer. The transducer output is measured and displayed through a projector for the class to see. Turning the lamp on causes the rubber band to heat up and shrink; the force transducer accordingly registers a higher force. TEMPERATURE AND EXPANSION.
UCB Index: 
Demo Diagram: