I'm on a physics excercise where it says i have to show that two powers are equal:

the rate at which gravitational energy is lost

and the electrical power dissipation

in a circuit which is falling trough the gravitational field and a magnetic field which is inducting current in the curcuit (has a resistance causing the dissipation).

Well not going into those details, how can i by simply saying that the forces are equal, the gravitational force and the "force due to the rod" (F=IlB) then the power is equal too?