INPHO

Consider a heavy rod mass $m$ and length $L$ in between the two light rods (perpendicular and fixed). The whole set up is in the horizontal plane. The heavy rod is given an initial angular velocity $\omega$ . Find $\omega$ such that the light rod always remains in contact with it and it comes to rest finally as shown. A magnetic field $B$ exists perpendicular to the plane. Let the resistance of the heavy rod be $R$ and that of the light rods be 0.

If $\omega = a \cdot \dfrac{B^2 L}{mR}$ , submit your answer as $a$ .