Question

How to calculate mean value of emf?

Answer 1

Answer:

YOUR ANSWER IS HERE

Explanation:

EMF Formula. The EMF or electromotive force is the energy supplied by a battery or a cell per coulomb (Q) of charge passing through it. The magnitude of emf is equal to V (potential difference) across the cell terminals when there is no current flowing through the circuit

Answer 2

Answer:

Explanation:The mean value or average value of AC over a complete cycle is zero. So we do not consider the average value of AC over one cycle. We therefore take the average value of AC over a half cycle only I.e. from t=0 to t=T/2

The average value of AC over a half cycle is that value of steady current that would send same amount of charge in same interval of time that would be sent by the DC in same time.

To calculate the mean value of ac, Let us consider an ac given by

rms the small amount of charge sent by an ac in small time dt is

mean value of ac

total charge carried by ac in half cycle is obtained by integrating equation ii from t = 0 to t = T/2

If Im be the average ac then charge carried by it in half cycle is

Now from equation iii and iv we get

Similarly the average value of ac over negative half cycle (t = T/2 to t = T) is

Therefore the average ac over a complete cycle is zero.

Similarly the average value of alternating emf over a half cycle is