Question

find the expression of the stored in the capacitor also find the energy lost in the when the charged capacitor is disconnected from the source and
connected in parallel with the uncharged capacitor where does this loss of energy appear

Answer 1

find the expression of the stored in the capacitor also find the energy lost in the when the charged capacitor is disconnected from the source and  

connected in parallel with the uncharged capacitor where does this loss of energy appear

Answer 2

The expression of the energy stored in the capacitor  is 1/2C1V^2.

1. The energy lost when the charged capacitor is disconnected from the source and connected in parallel with the uncharged capacitor of same capacitance is 1/2C1C2v^2/(C1+C2)

  • We know by conservation of energy,  energy can neither be ceated nor be lost.

  • If we connect an uncharged capacitor to a charged capacitor,  voltage across both cap is same and total charge remains same.

 • Q1 + Q2 = Q = C1V

 • C1Vo + C2Vo = C1V

 • Vo = C1V/C1 + C2

Energy in both the capacitors = 1/2(C1+C2)Vo^2 = 1/2( C1V)^2/C1 + C2

Loss of energy = 1/2C1V^2 - new energy = 1/2C1C2V^2/(C1 + C2)

 

2. This energy is lost as heat  in the wires which connect the capacitors.

• Total charge is conserved here