5F20.85 - Frequency in Parallel and Series Circuits

Parallel RC Circuit
Series RC Circuit
Code Number:
Demo Title:
Frequency in Parallel and Series Circuits
Frequency in RC and RL circuits
Area of Study:
Electricity & Magnetism
Decade Capacitor Box, Decade Inductor, #40 light bulb in socket, Wave Generator, Pyle PT-610 Amplifier with 70 volt outputs.

Connect the 70 volt outputs of the amplifier to the light bulb and plug the wave generator into the Aux. input.  Set the wave generator to the 0 to 11 KHz. scale.  Turn the Aux. input channel up to just over 1/2 way and the master volume on the amplifier to about 10 % on or until the light bulb is at maximum brightness.  WARNING:  TOO MUCH AMPLIFICATION WILL BURN OUT THE LIGHT BULB.  Put either the capacitor set at .3 uf or the inductor set at 100 mH in parallel with the light bulb.  Note that in this configuration you can adjust the frequency between 1K and 11K without changing the brightness of the light bulb.  Now connect either the capacitor or inductor in series with the light bulb.  Note that with the capacitor in series the bulb will get brighter as the frequency goes up, and that with the inductor in series the bulb will come on at a low frequency and go out again after the frequency goes up several KHz.  

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