A light, frictionless conducting rod can slide on two horizontal parallel rails…

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

A light, frictionless conducting rod can slide on two horizontal parallel rails

0.60\,\text{m}

apart. The rails are connected at one end through a resistor of

0.40\,\Omega

. The region is filled with a uniform vertical magnetic field of magnitude

0.50\,\text{T}

. Starting from rest, the rod is pulled forward by a constant horizontal force of

1.0\,\text{N}

. After some time, it attains a steady (terminal) speed when the magnetic force balances the applied force. Determine this steady speed. (a)

6.7\,\text{m\,s}^{-1}

(b)

2.2\,\text{m\,s}^{-1}

(c)

4.4\,\text{m\,s}^{-1}

(d)

8.9\,\text{m\,s}^{-1}