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Question
The current generator Ig' shown in figure, sends a constant current i through the circuit. The wire cd is fixed and ab is made to slide on the smooth, thick rails with a constant velocity v towards right. Each of these wires has resistance r. Find the current through the wire cd.
Solution
Current passing through the circuit initially = i
Initial emf = ir
Emf induced due to motion of ab, e = Blv
Net emf, enet= ir − Blv
Net resistance = 2r
Thus, the current passing through the circuit is `(ir-Blv)/(2r)`
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