Physics - Magnetism Question with Solution | TestHub

A small ring with mass m and charge +q is placed on a vertical uniform cylindrical straight rod. The ring can slide on the straight rod, and the friction coefficient is $\mu$. There is a uniform electric field horizontally to the right in the space, and the field strength is E ; the magnetic induction intensity of the uniform magnetic field to the outside of the paper is B , as shown in Figure. The small ring starts to move downward from rest. The maximum speed of the small ring is ( $\mathrm{B}=1\mathrm{T},\mathrm{m}=10^{-6}\mathrm{kg},\mathrm{g}=10\mathrm{m}/{\mathrm{s}}^2,\mu =0.2,\mathrm{q}=10^{-6}\mathrm{C},\mathrm{E}=2\mathrm{N}/\mathrm{C}$ )