Q. The number of turns in the coil of an ac generator is 5000 and the area of the coil is $0.25m^{2}$. The coil is rotated at the rate of $100\ cycles/sec$ in a magnetic field of $0.2\ W/m^{2}$. The peak value of the emf generated is nearly
A) $786\ kV$
B) $440\ kV$
C) $220\ kV$
D) $157.1\ kV$
Explanation
(d) $e_{0} = \omega NBA = (2\pi v)NBA$
$= 2 \times 3.14 \times 1000 \times 5000 \times 0.2 \times 0.25 = 157\ kV$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.