Question

What is the area of a periodic signal in a periodic interval?

(a) It depends on the situation

(b) It is same as the area in the previous interval

(c) It is different in different situations

(d) It is the square of the fundamental period

I had been asked this question by my school principal while I was bunking the class.

This intriguing question comes from Periodic Signals topic in portion Fourier Series of Signals and Systems

Answer 1

Right option is (b) It is same as the area in the previous interval

The best I can explain: The area of any periodic signal in any interval is the same. Hence it is same as the previous interval. This results from the fact that a periodic signal takes same values at the intervals of T.