- The
**average current**flowing through an element in an**AC circuit is zero.**

Prof: |

- The average voltage, like the current, is also zero.

- The
**average power**delivered by an AC circuit**is not zero**as any one who has been shocked by an AC circuit can attest.

- AC ammeters and volt meters are designed to output the
**root-mean-square average**of the current or voltage rather than the maximum values.

- The difference between maximum and rms values of the current or voltage is just the square root of 2:

Prof: |
One way to show that with out doing any integrationis to first note that This is true since both functions have the same shape, one is just the other translated by 1/4 of the period Taking the average of the trigonometric identity, |