Magnetism Question 5
Question: Assertion : When radius of circular loop carrying current is doubled, its magnetic moment becomes four times. Reason : Magnetic moment depends on area of the loop.
Options:
A) If both assertion and reason are true but reason is not the correct explanation of the assertion.
B) If both assertion and reason are true and the reason is the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
Show Answer
Answer:
Correct Answer: B
Solution:
Magnetic dipole moment of the current loop = Ampere turns ´ Area of the coil Initially magnetic moment M = ipr2, new magnetic moment $ M’=i,\pi {{(2r)}^{2}} $
$ =4i,(\pi r^{2})=4M. $ So magnetic moment becomes four times when radius is doubled.
BETA
