Question

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. 198V
• B. 386V
• C. 56V
• D. None of these

Answer 1

Answer: (A)

198V

Answer 2

$V_{av} = \frac{2}{\pi}V_{0} = \frac{2}{\pi} \times (V_{rms} \times \sqrt{2}) = \frac{2\sqrt{2}}{\pi}.V_{rms}$

$= \frac{2\sqrt{2}}{\pi} \times 220 = 198\mspace{6mu} V$