Q.

Two identical capacitors C1 and C2 of equal capacitance are connected as shown in the circuit. Terminals a and b of the key k are connected to charge capacitor C1 using a battery of emf V volt. Now disconnecting a and b, the terminals b and c are connected. Due to this, what will be the percentage loss of energy       [2019]


 

1 75%  
2 0%  
3 50%  
4 25%  

Ans.

(3)

As we know that, loss of electrostatic energy, 

Eloss=12C1C2(C1+C2)V2=12×C22CV2

          =12(12CV2)=12E                 [∵C1=C2=C]

    Percentage of loss of energy=12EE×100%

           =12×100%=50%