(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What fraction of the energy of a square wave is in its fundamental? In its first five harmonics? First seven? Nine?

2. Relevant equations

the fourier series of a square wave...

v(t) = ( 4V / pi ) ( sinw0t + 1/3sin3w0t + 1/5sin5w0t + ... )

also given a graph showing the frequency spectrum of pulses

at w0 4V/pi

at 3w0 1/3(4V/pi)

at 5w0 1/5(4V/pi)

at 7w0 1/7(4v/pi)

...

3. The attempt at a solution

Been working on this and wasn't able to find a solution... I'm not sure how I'm supposed to derive an equation for energy that I can use to solve the problem... I know that E is the infinitely bounded integral of (v^2)/R dt, but not sure how to apply this here with a fourier transform made up of discrete pulses.

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# Homework Help: Simple question re harmonics

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