A rectangular coil of area and turns is pivoted about one of its vertical sides

PHYSICS · Subjective · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism

Problem

A rectangular coil of area

5.0\times10^{-4}\,\text{m}^2

and

60

turns is pivoted about one of its vertical sides. The coil is in a radial horizontal magnetic field of

9\times10^{-3}\,\text{T}

. What is the torsional constant of the spring connected to the coil if a current of

0.20\,\text{mA}

produces an angular deflection of

18^\circ