Q. The frequency of an alternating voltage is $50\ cycles/sec$ and its amplitude is $120V$. Then the $r.m.s.$ value of voltage is
A) $101.3V$
B) 84.8$V$
C) 70.7$V$
D) 56.5$V$
Explanation
(b) $V_{rms} = \frac{V_{0}}{\sqrt{2}} = \frac{120}{1.414} = 84.8\ V$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.