Two large metal sheets carry surface currents as depicted in the figure. The current through a strip of width dl is given by K , dl , where K is a constant. A particle with charge q and mass m is projected from point Q in a direction going into the plane of the diagram. It is observed to describe a circle of radius r between the two plates. Determine the speed of the charged particle.

Step-by-step solution

The magnetic field produced by a single large metal sheet carrying a surface current density K is given by B = ₀ K 2 . For the top sheet, the current is directed out of the plane of the paper. According to the right-hand rule, the magnetic field produced by the top sheet at point Q (which lies below it) is directed towards the right, with magnitude B₁ = ₀ K 2 . For the bottom sheet, the current is directed into the plane of the paper. The magnetic field produced by the bottom sheet at point Q (which lies above it)