First slide

Redistribution of charges and concept of common potential

Question

An uncharged parallel plate capacitor having a dielectric of dielectric constant K is connected to a similar air cored parallel plate capacitor charged to a potential V₀. The two share the charge, and the common potential becomes V. The dielectric constant K is

Moderate

A

$\frac{V_{0}}{V} - 1$
B

$\frac{V_{0}}{V} + 1$
C

$\frac{V}{V_{0}} - 1$
D

$\frac{V}{V_{0}} + 1$

Solution

$C_{1} = C, V_{1} = V_{0}, C_{2} = KC, V_{2} = 0, and V_{common} = V$
We know that
$V_{common} = \frac{C_{1} V_{1} + C_{2} V_{2}}{C_{1} + C_{2}}$
$∴ V = \frac{{CV}_{0} + KC \times O}{C + KC}$
or $K = \frac{V_{0}}{V} - 1$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App