====== Driven and Damped Torsional Pendulum ======
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A torsional pendulum is driven by a variable-speed motor. The amplitude of the oscillations increases dramatically when the pendulum is driven at its resonant frequency. The body of the pendulum consists of copper and passes through a gap in a solenoid. Applying a current to the solenoid damps the motion of the pendulum due to the creation of eddy currents in the copper.

===Set up===

Connect the 0-24V leads across the bottom two leads (supply represented by Ux (in parallel with the motor, M). The top two leads are for the potentiometer controlling the electromagnet current. Connect the top two leads to the leads of the electromagnet for damping. Damping can be controlled with the knobs on top. 

M1

set-up details

PIRA DCS 3A60.55