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?