Two plates of a parallel plate capacitor after being charged from a constant voltage source are separated apart by means of insulated handles, then the

The correct answer is: C. Charge on the capacitor decreases.

When the plates of a parallel plate capacitor are separated, the electric field between the plates decreases. This is because the charge on the plates is spread out over a larger area. The electric field is proportional to the charge, so the decrease in electric field means that the charge on the plates must also decrease.

Here is a more detailed explanation of each option:

• Option A: Voltage across the plates increases. This is incorrect because the voltage across the plates is determined by the charge on the plates and the capacitance of the capacitor. The capacitance of the capacitor is a constant, so the voltage across the plates cannot change when the charge on the plates changes.
• Option B: Voltage across the plates decreases. This is incorrect for the same reason as Option A.
• Option C: Charge on the capacitor decreases. This is correct because the electric field between the plates decreases when the plates are separated. The electric field is proportional to the charge, so the decrease in electric field means that the charge on the plates must also decrease.
• Option D: Charge on the capacitor increases. This is incorrect because the charge on the plates decreases when the plates are separated.