consider a sin wave(adsbygoogle = window.adsbygoogle || []).push({});

to find the average of this function over interval 2pi, why not just do...

$$\frac{1}{2\pi}\int |sinx|dx$$

this turns out to be..

$$\frac{4}{2\pi}= 0.63619$$

the whole purpose of squaring and then sqrt'ing at the end is to make sure there are no negative values. this would be fine if its value came out to be the same as the average of the absolute value (which is what i thought we were trying to find in the first place), but the value is different.

so.. i guess i have two questions:

1.) is 0.636 more correct to use as an avg than 0.702?

2.)why do we always use RMS value in science as opposed to the ACTUAL avg (of the absolute)?

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# Why use RMS for averages?

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