# Expected power of a square wave

Tjvelcro

## Homework Statement

What is the expected power of the first three frequency components of a square wave with an amplitude of 0.2V?

## Homework Equations

None that I know of :(

## The Attempt at a Solution

I'm not sure where to start with this since it seems to give me so little information. I think I may have to use V(rms) but I'm not sure. Any help or hints would be appeciated.

Tjvelcro

rootX
Do you know equation of power for periodic waves?

Tjvelcro
No, Im not sure what that equation is... tried to look in my book but cannot find it.

rootX
$$\frac{1}{T}\int_{0}^{T}|x(t)|^2\,dt$$

Above is the power equation.

However, it seems like you are attempting to finding power contained in first three frequency components of square wave. I only read the title thought you want power of square wave. I would suggest you to look into .. Parseval's Theorem (http://engnet.anu.edu.au/DEcourses/engn2228/Lectures/Lecture15.pdf slide 11).

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