Answer:
(a) Magnetic field at the center of the loop is 4.08 x 10⁻⁵ T
(b) Magnetic field at the axis of the loop is 5.09 x 10⁻⁹ T
Step-by-step explanation:
Given :
Diameter of the circular loop = 2 cm
Radius of the circular loop, R = 1 cm = 0.01 m
Current flowing through the circular wire, I = 650 mA = 650 x 10⁻³ A
(a) Magnetic field at the center of circular loop is determine by the relation:

Here μ₀ is vacuum permeability constant and its value is 4π x 10⁻⁷ T m²/A.
Substitute the suitable values in the above equation.

B = 4.08 x 10⁻⁵ T
(b) Distance from the center of the loop, z = 20 cm = 0.2 m
Magnetic field at the point on the axis of the loop is determine by the relation:


B = 5.09 x 10⁻⁹ T