What is the frequency of the third harmonic on a 60 Hz power distribution line?

To determine the frequency of the third harmonic on a 60 Hz power distribution line, one must understand the concept of harmonics in electrical systems. Harmonics are integer multiples of a fundamental frequency. In this case, the fundamental frequency is 60 Hz.

To calculate the frequency of the third harmonic, you multiply the fundamental frequency by 3.

So the calculation is:

Third harmonic frequency = 3 × 60 Hz = 180 Hz.

Therefore, the correct answer is 180 Hz, as this reflects the frequency that corresponds to the third harmonic in a system with a fundamental frequency of 60 Hz. This concept is crucial when analyzing signals in power systems, as harmonics can affect the performance and efficiency of electrical circuits.