# Class 12 Physics Electrostatic Potential and Capacitance: NCERT Solutions for Question 11

This page focuses on the detailed Electrostatic Potential and Capacitance question answers for Class 12 Physics Electrostatic Potential and Capacitance, addressing the question: 'A 600 pF capacitor is charged by a 200 V supply. It is then disconnected from the supply and is connected to another uncharged 600 pF capacitor. How much electrostatic energy is lost in the process?'. The solution provides a thorough breakdown of the question, highlighting key concepts and approaches to arrive at the correct answer. This easy-to-understand explanation will help students develop better problem-solving skills, reinforcing their understanding of the chapter and aiding in exam preparation.
Question 11

## A 600 pF capacitor is charged by a 200 V supply. It is then disconnected from the supply and is connected to another uncharged 600 pF capacitor. How much electrostatic energy is lost in the process?

Capacitance of the capacitor, C = 600 pF

Potential difference, V = 200 V

Electrostatic energy stored in the capacitor is given by,

If supply is disconnected from the capacitor and another capacitor of capacitance C = 600 pF is connected to it, then equivalent capacitance (C') of the combination is given by,

New electrostatic energy can be calculated as

Loss in electrostatic enegy = E - E'

= 1.2 x 10-5  -  0.6 x 10-5

= 0.6 x 10-5

= 6 x 10-6

Therefore, the electrostatic energy lost in the process is 6 x 10-6 J.