Question

As a result of polarization, surface charge density of capacitor:
A. Increases B. Decreases
C. Remains constant D. None of these

Answer 1

Answer:

As a result of polarisation surface charge density of capacitor increase

Answer 2

Answer:

B. Decreases

Explanation:

We have a capacitor let's say of capacitance C and is charged by Voltage say V. Then the voltage is disconnected and a dielectric of dielectric constant say k is inserted fully between the plates of parallel plate capacitor. We are asked to find the change in charge stored by the capacitor and change in voltage. Now what I am not getting is why does charge stored in capacitor remain constant. The surface charge density decreases due to polarisation of dielectric and so the net charge on the plates should decrease yet we are considering charge to be constant