A metal rod of length slides with constant speed on two parallel conducting rails…
PHYSICS · Subjective · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
A metal rod of length 0.40m slides with constant speed 6.0ms−1 on two parallel conducting rails that are 0.40m apart. The arrangement is in a uniform magnetic field of 0.50T directed perpendicular to the plane of the rails. The total resistance of the closed circuit (rails, rod and connecting path) is 0.20Ω.
(a) Calculate the magnitude of the emf induced in the rod.
(b) Determine the current in the circuit.
(c) Find the magnetic force opposing the motion of the rod.
(d) Show that the mechanical power required to keep the rod moving at the given speed equals the electrical power dissipated in the circuit.