1. Feb 26, 2005

airkapp

The generator of a car idling at 950 rpm produces 12.4 V. What will the output be at a rotation speed of 2500 rpm assuming nothing else changes?

I'm guessing that is easier and I'm looking to make it harder. I can't find anything in my textbook involving rpm. I'm thinkin to use this formula
E = NBAw but I'm actually not quit sure how to approach the problem.

is N my rpm? and then I do an initial rpm and final rpm sequence?

2. Feb 26, 2005

vincentchan

N is number of loop... $$\omega$$ is the angular velocity.....

the rpm (rotation per minute, or radian per minute) is directly proportional to the angular velocity.... does that make sense to you?

3. Feb 26, 2005

airkapp

so i could set this up as a proportion?

950/12.4 V =2500/x Volts ?

thanks.

4. Feb 26, 2005

ramollari

I think you should also consider the back EMF.

5. Feb 26, 2005

airkapp

sorry, I'm not following. If all things remain constant why would I consider that? The back emf oppose the motion (Lenz's law) correct, but if everything remains constant...