A circular loop of wire 10 cm in radius carries a current of 20 A.The axial magnetic field 15 cm from the center of the loop is approximately
A)37 $\mu$T
B)13 $\mu$T
C)21 $\mu$T
D)41 $\mu$T
E)18 $\mu$T

Question

Quizplus · Accepted Answer

The formula for the magnetic field at a point on the axis of a circular loop of radius R, carrying a current I, is given by:
B = (μ0I/2)(R^2/(R^2 + x^2)^(3/2))

where μ0 is the permeability of free space and x is the distance from the center of the loop to the point on the axis.

Substituting the given values, we get:

B = (4π × 10^-7 × 20/2)(0.1^2/(0.1^2 + 0.15^2)^(3/2))
  = 21 μT (or 21 × 10^-6 T)

Therefore, the answer is C.

A Circular Loop of Wire 10 Cm in Radius Carries μ\muμ

A Circular Loop of Wire 10 Cm in Radius Carries $\mu$