Magnetic Effects Of Current Question 216
Question: A current i flows in a circular coil of radius r. If the coil is placed in a uniform magnetic field B with its plane parallel to the field, magnitude of the torque that acts on the coil is [MP PET 2001]
Options:
A) Zero
B) $ 2\pi ,r,i,B $
C) $ \pi ,r^{2},i,B $
D) $ 2\pi ,r^{2},i,B $
Show Answer
Answer:
Correct Answer: C
Solution:
As shown in the following figure, the given situation is similar to a bar magnet placed in a uniform magnetic field perpendicularly. Hence torque on it $ \tau =MB\sin 90{}^\circ =(i\pi r^{2})B $
BETA
