A magnetic needle of magnetic moment 6 .7 × 10 - 2 A m 2 and moment of inertia 7 .5 × 10 - 6 kg m 2 is performing simple harmonic oscillations in a magnetic field of 0 . 01 T . Time taken for 10 complete oscillations is:

Step-by-step solution

Time period of oscillating magnetic needle is T = 2 π I M B = 2 π 7.5 × 10 - 6 6.7 × 10 - 2 × 0.01   sec = 0.6647   sec Time for oscillations, t = 10   T = 6.647   sec ⁡ = 6.65   sec