JEE Main20241 Feb 2024Evening ShiftPhysicsMagnetic Effects of CurrentActual
A moving coil galvanometer has 100 turns and each turn has an area of 2 . 0 cm 2 . The magnetic field produced by the magnet is 0 . 01 T and the deflection in the coil is 0 . 05 radian when a current of 10 mA is passed through it. The torsional constant of the suspension wire is x × 10 - 5 N - m / rad . The value of x is ______ .
Correct answer
0
Step-by-step solution
Torque produced in a moving coil galvanometer is, τ = BINAsin ϕ . Let torsional constant of the suspension wire be C , then C θ = BINAsin 90 ° ⇒ C = B I N A θ = 0 . 01 × 10 × 10 - 3 × 100 × 2 × 10 - 4 0 . 05 = 4 × 10 - 5 N - m / rad . Therefore, x = 4 .