A magnetic dipole of magnetic moment ( 6 10⁻² Am ² ) and moment of inertia ( 12 10⁻⁶ ~kg ~m ² ) performs oscillations in a magnetic field of ( 2 10⁻² ~T ). The time taken by the dipole to complete ( 20 ) oscillations is ( ( 3) )

Step-by-step solution

Given, magnetic moment, ( M=6 10⁻² Am ² ), moment of inertia, ( I=12 10⁻⁶ kgm ² ); magnetic field, ( B=2 10⁻² T ); number of oscillations ( =20 ). Now, time period of one oscillation, ( t=2 l B M ) ( t=2 12 10⁻⁶ 2 10⁻² 6 10⁻² =2 10⁻¹ ) Therefore, time taken by dipole to complete ( 20 ) oscillations is ( T=20 t=20 2 10⁻¹=20 2 3 1 10 =12 s )