Q. If an ac main supply is given to be $220\ V$. What would be the average $e.$m.f. during a positive half cycle
A) 198$V$
B) 386$V$
C) 256$V$
D) None of these
Explanation
(a) $V_{av} = \frac{2}{\pi}\ V_{0} = \frac{2}{\pi} \times \left( V_{rms} \times \sqrt{2} \right) = \frac{2\sqrt{2}}{\pi}.V_{rms}$
$= \frac{2\sqrt{2}}{\pi} \times 220 = 198\ V$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.