Suppose that the emf from a rod moving in a magnetic field was used to supply the current to illuminate a light bulb in a circuit, and the force needed to keep the rod moving is . What happens to the force needed drive the motion of the rod if the light bulb is removed?a. No force is neededb. there is no longer a magnetic force to oppose the motion. c. It is the same as when the bulb is in the circuit. d. A larger force is needed to the keep the rod moving