JEE Main202431 Jan 2024Evening ShiftPhysicsMagnetic Effects of CurrentActual
A uniform magnetic field of 2 × 10 - 3 T acts along positive Y-direction. A rectangular loop of sides 20 cm and 10 cm with current of 5 A is in Y-Z plane. The current is in anticlockwise sense with reference to negative X axis. Magnitude and direction of the torque is :
Options
- A2 × 10 - 4 N m along positive Z –direction
- B2 × 10 - 4 N m along negative Z-direction
- C2 × 10 - 4 N m along positive X-direction
- D2 × 10 - 4 N m along positive Y-direction
Correct answer
B. 2 × 10 - 4 N m along negative Z-direction
Step-by-step solution
Magnetic moment is given by, M → = i A → = 5 × 0 . 2 × 0 . 1 - i ^ = 0 . 1 - i ^ τ → = M → × B → = 0 .1 − i ^ × 2 × 10 − 3 j ^ = 2 × 10 − 4 − k ^ N m