In a parallel-plate capacitor, the region between the plates is filled

1.	In a parallel-plate capacitor, the region between the plates is filled by a dielectric slab. The capacitor is connected to a cell and the slab is taken out. (a) Some charge is drawn from the cell.(b) Some charge is returned to the cell.(c) The potential difference across the capacitor is reduced. (d) No work is done by an external agent in taking the slab out.
Answer» Correct Answer is: (b) Some charge is returned to the cell. When the dielectric slab is taken out, the capacitance decreases. Hence charge decreases, and the difference in charge is returned to the cell.

In a parallel-plate capacitor, the region between the plates is filled by a dielectric slab. The capacitor is connected to a cell and the slab is taken out. (a) Some charge is drawn from the cell.(b) Some charge is returned to the cell.(c) The potential difference across the capacitor is reduced. (d) No work is done by an external agent in taking the slab out.

Answer»

Correct Answer is: (b) Some charge is returned to the cell.

When the dielectric slab is taken out, the capacitance decreases. Hence charge decreases, and the difference in charge is returned to the cell.

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