Question

Three rings, each having equal radius R, are placed mutually perpendicular to each other and each having its centre at the origin of coordinate system. If current I is flowing through each ring, then the magnitude of the magnetic field at the common centre is

A. `sqrt(3)(mu_(3)I)/(2R)`
B. zero
C. `(sqrt(2)-1)(mu_(0)I)/(2R)`
D. `(sqrt(3)-sqrt(2))(mu_(0)I)/(2R)`

Answer 1

Correct Answer - A
`vec(B)=(mu_(0)I)/(2R)(+-hat(i))+(mu_(0)I)/(2R)(+-hat(j))+(mu_(0)I)/(2R)(+-hat(k))`
`|vec(B)|=(mu_(0)I)/(2R)sqrt(3)`