Question

A parallel plate capacitor is charged fully by using a battery . Then, without disconnecting the battery, the plates are moved further apart. Then,

• A. the charge on the capacitor increases
• B. the voltage difference between the plates decreases
• C. the capacitance increases
• D. the electrostatic energy stored in the capacitor decreases

Answer 1

Answer: (D)

As plates are moved far away further, capacity of capacitor $\left(C=\frac{{\epsilon }_{o}A}{d}\right)$ decreases.
As battery remains connected during this activity,
potential difference between plates remains same.
So, the charge on plates $(Q=CV)$ decreases .
Also, energy of capacitor $(U=\frac{1}{2}C{V}^2)$ decreases as capacitance decreases.