Magnetic Effects Of Current Question 61

Question: One metre length of wire carries a constant current. The wire is bent to form a circular loop. The magnetic field at the centre of this loop is B. The same is now bent to form a circular loop of smaller radius to have four turns in the loop. The magnetic field at the centre of this new loop is

Options:

A) 4 B

B) 16 B

C) $ B/2 $

D) $ B/4 $

Show Answer

Answer:

Correct Answer: B

Solution:

$ {B}’=n^{2}B\Rightarrow {B}’={{(4)}^{2}}B={B}’=16B $