A semi-circular loop of radius 30 cm wire carries current 6 A. An uniform magnetic field 0.5 T is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire ?

Options

A. 0.9 N
B. 1.8 N
C. 0.8 N
D. 1.4 N

Answer

B

Explanation

Given, the radius of a circular loop,
`R=30xx10^(-2)m`
current, `I=6A` and magnetic field, `B=0.5T`.
Force exerted on the wire,
`F=ILBsin theta`
`rArr F=6xx2xx30xx10^(-2)xx0.5xxsin 90^(@)` [ `:.theta=90^(@) and sin 90^(@)=1`]
`rArr F=1.8 N`
Hence, the correct option is (b).