Electro Magnetic Induction And Alternating Currents Question 275
Question: In a region of uniform magnetic induction $ B={{10}^{-2}},tesla $ , a circular coil of radius 30 cm and resistance p2 ohm is rotated about an axis which is perpendicular to the direction of B and which forms a diameter of the coil. If the coil rotates at 200 rpm the amplitude of the alternating current induced in the coil is [CBSE PMT 1990]
Options:
A) 4p2 mA
B) 30 mA
C) 6 mA
D) 200 mA
Show Answer
Answer:
Correct Answer: C
Solution:
Amplitude of the current $ i_{0}=\frac{e_{0}}{R}=\frac{\omega NBA}{R}=\frac{2\pi \nu NB(\pi r^{2})}{R} $ $ i_{0}=\frac{2\pi \times 1\times {{10}^{-2}}\times \pi {{(0.3)}^{2}}}{{{\pi }^{2}}}=6\times {{10}^{-3}}A=6mA $
