Thread: Cheapest and easiest way to slow down a motor
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Unread 20-12-2005, 01:03
sanddrag sanddrag is offline
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Re: Cheapest and easiest way to slow down a motor
Quote:
Originally Posted by sciguy125
Kirchoff's Voltage Law: sum of the voltage drops around a loop is equal to the sources

You have a 12V source and two drops. You can get the voltage across the resistor with Ohm's Law: V=IR. Whatever's left is the voltage across the motor.

12 = IR + V (V = motor voltage)

Notice that the voltage will change with the current.
So if I wanted the motor to run at 6 Volts and it draws 5 amps (estimate), I'd need a 1.2 Ohm resistor in series with it?
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