Question

circular coil of 50 turns and radius 7cm is placed in a uniform magnetic field of 4 T normal to the plane of the coil. If the current in the coil is 6A then total torque acting on the coil is
a) 14.78 Nm b) 0 c) 7.39 Nm d) 3.69 Nm​

Answer 1

answer : option c zero

ans option c

Answer 2

The total torque acting on the coil is b) 0

The given data;

• Number of turns in the coil(n) = 50
• radius of coil=$7cm=7 \times 10^{-2} m$  
• current in the coil=6A
• magnetic field = 4Tesla

Explanation:

   Torque$( \tau )$ = $MBSin \theta =IABSin \theta$

• The magnetic field is normal to the plane, and the magnetic moment is similarly normal to the plane, hence the angle between M and B is zero.

• $( \tau )=MBSin \theta =0$  
• value of torque acting on the loop becomes zero
• a circular coil of 50 turns and a radius 7cm is placed in a uniform magnetic field of 4t normal to the plane of the coil
• if the current in the coil is 6A then,
• the total torque acting on the coil is zero (0)