First slide
Capacitors and capacitance
Question

A parallel plate capacitor is connected to a battery. The plates are pulled apart with uniform speed. If x is the separation between the plates, then the rate of change of electrostatic energy of the capacitor is proportional to 

Moderate
Solution

The capacitance of capacitor C is ε0A/x.Charge on capacitor 

q=CV=ε0AVx;U=12qV=12ε0AV2x

So dUdt=12ε0AV2-1x2dxdt

=12ε0AV2v-1x2

From the earlier expressions,

dUdt1x2

Get Instant Solutions
When in doubt download our app. Now available Google Play Store- Doubts App
Download Now
Doubts App