Lab #10- Electric Motorcycle showed how two transistors can be used to create an oscillating signal that when sent through a speaker, sounds similar to that of a motorcycle. The speed of the motorcycle can be controlled through the use of a potentiometer or rheostat which varies the resistance passing through the transistors. This circuit works because the opposite bias of the transistors caused the polarity of the signal to change rapidly which in turn causes the electromagnet to move back and forth, bouncing off of the speaker cones as it does so. The capacitor in the circuit works to keep the signal at a constant level so that the sound coming from the speaker sounds the same every time the signal oscillates.
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