A 12pF capacitor is connected to a 50V battery. How much electrostatic energy is stored in the capacitor?
Step 1 : Formula of Energy stored in capacitor
The Energy stored U in a capacitor of Capacitance C, Charge Q and Potential Difference V across it is given by:
U=12CV2=Q22C=12QV ....(1)
Step 2: Calculation of Energy stored
Given, Capacitance C=12pF=12×10−12F
And Potential difference V=50V
So using the first formula from Equation (1), we get Energy stored as:
U=12CV2=12×[12×10−12F]×[(50V)2]=15×10−9J
U=15nJ
Hence Energy stored in capacitor is 15nJ.