Final answer:
A two-pole generator must rotate at 60 rotations per minute (rpm) to produce a frequency of 60 Hz.
Step-by-step explanation:
In order to produce a frequency of 60 Hz, a two-pole generator must rotate at a speed such that each complete rotation (360 degrees) takes 1/60th of a second. This means that the generator must complete 60 rotations in one second.
Since there are 60 seconds in a minute, the generator must rotate at a speed of 60 rotations per minute (rpm) to produce a frequency of 60 Hz.