PHYS 2212 Module 4.3

Energy Stored in a Capacitor

Recommended Reading

4.3 Energy Stored in a Capacitor

Learning Objectives

By the end of this section, you will be able to:

  • Explain how energy is stored in a capacitor
  • Use energy relations to determine the energy stored in a capacitor network

Energy Stored in a Capacitor


Practice 4.3.1
You have three capacitors and a battery. In which of the following combinations of the three capacitors is the maximum possible energy stored when the combination is connected to the battery?
Check your answer: B. parallel

Example problem: Work through this problem on your own. Afterward, you can watch my video solution to check your results.

A spherical capacitor is formed from two concentric spherical conducting shells separated by vacuum. The inner sphere has radius 10.0 cm, and the separation between the spheres is 1.50 cm. The magnitude of the charge on each sphere is 3.30 nC.

(a) What is the magnitude of the potential difference ∆V between the two spheres?

(b) What is the electric-field energy (in nJ) stored in the capacitor?