Magnetism Question 195
Question: A straight wire carrying current i is turned into a circular loop. If the magnitude of magnetic moment associated with it in M.K.S. unit is M, the length of wire will be
[MP PET 1999]
Options:
A) $ 4\pi iM $
B) $ \sqrt{\frac{4\pi M}{i}} $
C) $ \sqrt{\frac{4\pi i}{M}} $
D) $ \frac{M\pi }{4i} $
Show Answer
Answer:
Correct Answer: B
Solution:
Magnetic moment of circular loop carrying current $ M=IA=I( \pi R^{2} )=I\pi {{( \frac{L}{2\pi } )}^{2}}=\frac{IL^{2}}{4\pi }\Rightarrow L=\sqrt{\frac{4\pi M}{I}} $
BETA
