A generator rotating at 100rpm makes 1.24V. What will the output be at 250rpm? Which Equation to use as well?

Question

A generator rotating at 100rpm makes 1.24V. What will the output be at 250rpm? I can't seem to use any of my equations to figure this out. Which one do you use?

Answer 1

Assuming these are open-circuit voltages, the voltage is proportional to rotation rate, as specified by Faraday's law (ref.). So E = 1.24 * 250/100.