Problem 3.303

A connector \(A B\) can slide without friction along a \PiIshaped conductor located in a horizontal plane (Fig. 3.89). The connector has a length \(l,\) mass \(m,\) and resistance \(R .\) The whole system is located in a uniform magnetic field of induction \(B\) directed vertically. At the moment \(t=0\) a constant horizontal force \(F\) starts acting on the connector shifting it translationwise to the right. Find how the velocity of the connector varies with time \(t .\) The inductance of the loop and the resistance of the Tl-shaped conductor are assumed to be negligible.