Question

Determine (a) the maximum voltage that can be applied to a Teflon-filled parallel-plate capacitor having a plate area of 5.7 cm2 and an insulation thickness of 0.30 mm.

Determine (b) the maximum voltage that can be applied to a Air-filled parallel-plate capacitor having a plate area of 5.7 cm² and an insulation thickness of 0.30 mm.

Answer 1

As we know dielectric strength is the maximum amount of electric field (that is voltage across the separation length of capacitor plates).

Now, Vmax = dielectric strength * insulation thickness [insulation thickness between parallel plates in capacitor is dielectric]

a.) We know dielectric strength of Teflon is 80MV/m, d = 0.3 mm.

So, Vmax = 80 * 10^6 * 0.3 *10^-3 [1 MV =10^6 V and 1mm = 10^-3 m]

= 24000V

= 24KV ans. [1KV = 1000V]

b.) We know dielectric strength of air is 3*10^6 V/m, d= 0.3mm.

So, Vmax = 3 * 10^6 * 0.3 *10^-3 [1mm = 10^-3 m]

= 900V

= 0.9KV ans. [1KV = 1000V]