PURPOSE: To demonstrate the concept of resonance and the idea of phase shift at resonance.

DESCRIPTION: The oscilator motor is started so that the springs cause the air cart to travel slowly across the track. Slowly the speed of the motor is increased. The increase in motor speed causes the cart speed to increase and a reach resonance condition which causes the springs to begin to oscillate with a very large amplitude. This large amplitude in spring oscilations will cause a phase shift and the carts will try to fly off the track.

SUGGESTIONS: Be prepared to stop the oscilator motor at phase shift.

EQUIPMENT: Air cart setup with one glider, oscilator motor, springs, sail if required and a medium ring stand

SETUP TIME: 50 minutes

KEYWORDS: resonance phase shift