What is the mathematical formula for determining the frequency of an alternator?

The formula for determining the frequency of an alternator is F = (S × P) ÷ 120. In this equation, F represents the frequency in hertz (Hz), S is the number of poles in the alternator, and P is the speed of the alternator in revolutions per minute (RPM).

This relationship stems from the principle that the frequency produced by an alternator is directly related to the number of cycles it generates per minute. Each revolution contributes a set number of cycles based on the number of poles. The constant 120 serves as a conversion factor, allowing you to translate the RPM and poles into frequency. Specifically, with two poles, each full revolution generates one complete cycle, while more poles increase the cycles for the same RPM.

The other options do not accurately represent the relationship between the components involved in calculating frequency. For instance, the use of addition or subtraction in the other choices does not apply to how frequency, RPM, and pole count interact within the context of electrical engineering principles. Thus, the chosen formula effectively conveys the necessary calculations needed to determine alternator frequency.