Question

Explain what would happen if in the capacitor given in Exercise 2.8, a 3 mm thick mica sheet (of dielectric constant = 6) were inserted between the plates,

(a) While the voltage supply remained connected.

(b) After the supply was disconnected.

Answer 1

(a) Dielectric constant of the mica sheet, k = 6

Initial capacitance, C = 1.771 × 10⁻¹¹ F

Supply voltage, V = 100 V

Potential across the plates remains 100 V.

(b) Dielectric constant, k = 6

Initial capacitance, C = 1.771 × 10⁻¹¹ F

If supply voltage is removed, then there will be no effect on the amount of charge in the plates.

Charge = 1.771 × 10⁻⁹ C

Potential across the plates is given by,