Question

A 1.2 nf parallel-plate capacitor has an air gap between its plates. Its capacitance increases by 3.0 nf when the gap is filled by a dielectric
What is the dielectric constant of that dielectric?

Answer 1

Answer:2.5

Explanation:

Answer 2

Answer:

2.5

Explanation:

The capacitance of a parallel-plate capacitor filled with dielectric is given by

$C=kC_0$

where

k is the dielectric constant

$C_0$ is the capacitance of the capacitor without dielectric

In this problem,

$C_0=1.2 nF$ is the capacitance of the capacitor in air

$C=3.0 nF$ is the capacitance with the dielectric inserted

Solving the equation for k, we find

$k=\frac{C}{C_0}=\frac{3.0 nF}{1.2 nF}=2.5$