A circular loop of radius 4.0 cm is placed in a horizontal plane and carries an electric current of 5.0 A in the clockwise direction as seen from above. Find the magnetic field.
(a) at a point 3.0 cm above the center of the loop
(b) at a point 3.0 cm below the center of the loop.
Given:
Radius of circular loop(r) = 4 cm = 0.04 m
Current carried by it(i) = 5 A
Formula used:
Magnetic field at a distance x from the center of a current carrying circular loop(B),
Where
μ0 = magnetic permeability of vacuum = 4π x 10-7 T m A-1,
i = current carried by coil,
r = radius of coil
(a) To find the magnetic field 3 cm above the loop:
Magnetic field,
Here, x = 3 cm = 0.03 m
Hence, substituting the given values:
= 4.019 x 10-5 T (in the downward direction, by right hand thumb rule) (Ans)
(b) To find the magnetic field 3 cm below the loop:
Here, all the values are same as the previous part. Hence,
B = 4.019 x 10-5 T (in the upward direction, by right hand thumb rule)