A connector AB can slide without friction along a H-shaped 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 translation wise to the right. Find how the velocity of the connector varies with time t. The inductance of the loop and the resistance of the H-shaped conductor are assumed to be negligible.

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