Question
Question: Two circular coils X and Y having equal number of turns and carry equal currents in the same sense a...
Two circular coils X and Y having equal number of turns and carry equal currents in the same sense and subtend same solid angle at point O. If the smaller coil X is midway between O and Y, then if we represent the magnetic induction due to bigger coil Y at O as BY and due to smaller coil X at O as BX then
A
BXBY = 1
B
BXBY = 2
C
BXBY = 21
D
BXBY = 41
Answer
BXBY = 21
Explanation
Solution
By = 2[(2r)2+d2]3/2µ0NI(2r)2
Bx = 2[r2+(d/2)2]3/2µ0NI(r)2
Ž BxBy = 21