Electromagnetic Induction and Faraday's Law

AI Thread Summary
The discussion centers on calculating the output voltage of a car generator at different RPMs, specifically from 950 RPM producing 12.4 V to 2500 RPM. Participants explore the relationship between RPM and angular velocity, noting that RPM is directly proportional to angular velocity. A proposed method involves setting up a proportion to find the new voltage output. However, the consideration of back EMF is raised, which opposes the motion according to Lenz's law, leading to confusion about its relevance if other factors remain constant. The conversation highlights the complexities of applying Faraday's Law in practical scenarios.
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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?
 
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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?
 
vincentchan said:
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?


so i could set this up as a proportion?

950/12.4 V =2500/x Volts ?

thanks.
 
I think you should also consider the back EMF.
 
ramollari said:
I think you should also consider the back EMF.

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... :confused:
 
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