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.
Figure

Answer 1

EMF is Product of Field, Length and Speed.

Explanation:

Current passing through the circuit initially = i

Initial emf = ir

Emf induced due to motion of ab, e = Blv

Net emf, $e_n_e_t$ = ir − Blv

Net resistance = 2r

Thus, the current passing through the circuit is $\frac {ir - Blv}{2r}$