A conducting rod (OP) of length L rotates in form of a conical pendulum with an angular velocity `omega` about a fixed vertical axis passing through its end O. There is a uni- form magnetic field B in vertically downward direction. The rod makes an angle `theta` with the direction of the magnetic field. Calculate the emf induced across the ends of the rod. Which end is positive?

Answer

`(1)/(2) B omega L^(2) sin^(2) theta; O` is positive