Magnetic Effects Of Current Question 438
Question: The magnetic moment of a circular coil carrying current is
Options:
A) directly proportional to the length of the wire in the coil
B) inversely proportional to the length of the wire in the coil
C) directly proportional to the square of the length of the wire in the coil
D) inversely proportional to the square of the length of the wire in the coil
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ M=NiA\Rightarrow M\propto A\Rightarrow M\propto r^{2} $ $ [ As,\ell =2\pi r\Rightarrow \ell \propto r ] $
$ \Rightarrow ,M\propto {{\ell }^{2}} $
BETA
