In the figure shown the section EDGF is fixed. A rod having resistance ' R ' is moved with constant velocity in a uniform magnetic field B as shown in the figure. DE & FG are smooth and resistance less. Initially capacitor is uncharged. The charge on the capacitor:
remains constant
increases with time
increases linearly with time
oscillates.
As we have learned
Motional emf is given by
Now applying KVl for EDGF
or
Hence the charge on the capacitor increases with time.