Question

If an earthed plate is brought near a positively charged plate, the potential and capacity of charged plate respectively:

• A. increases, decreases
• B. decreases, increases
• C. decreases, decreases
• D. increases, increases

Answer 1

The correct option is B decreases, increases

When we bring a earthed plate near positively charged plate, negatiive charge is induced on the earthed plate.
Because of this negative charge, potential of positive plate decreases.

We know $Q=CV$
So, for constant charge $\left(Q\right)$, as $V$ decreases, $C$ increases.