Oscillation of a magnetic needle (vibration magnetometer)

2024 Re-NEET 1 question

1. The magnetic moment and moment of inertia of a magnetic needle as shown are, respectively, $1.0\times10^{-2}\ A\,m^2$ and $\dfrac{10^{-6}}{\pi^2}\ kg\,m^2$. If it completes 10 oscillations in 10 s, the magnitude of the magnetic field is