Advertisements
Advertisements
Question
A capacitor of capacity C1 is charged to the potential of V0. On disconnecting with the battery, it is connected with an uncharged capacitor of capacity C2 as shown in the adjoining figure. Find the ratio of energies before and after the connection of switch S.

Advertisements
Solution

Before the connection of switch S,
Initial energy `U_i = 1/2C_1V_0^2 + 1/2C_2O^2 = 1/2C_1V_0^2`
After the connection of switch S,
common potential V = `(C_1V_1 + C_2V_2)/(C_1 + C_2) = (C_1V_0)/(C_1 + C_2)`
Final energy = `U_f = 1/2(C_1 + C_2) (C_1V_0)^2/(C_1 + C_2)^2 = 1/2 (C_1^2V_0^2)/((C_1 + C_2))`
`U_f : U_i = C_1/((C_1 + C_2))`
APPEARS IN
RELATED QUESTIONS
Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel. Determine the charge on each capacitor if the combination is connected to a 100 V supply.
Suppose a charge +Q1 is given to the positive plate and a charge −Q2 to the negative plate of a capacitor. What is the "charge on the capacitor"?
The following figure shows two capacitors connected in series and joined to a battery. The graph shows the variation in potential as one moves from left to right on the branch containing the capacitors.

Find the charges on the four capacitors of capacitances 1 μF, 2 μF, 3 μF and 4 μF shown in the figure.

A capacitor of capacitance 5⋅00 µF is charged to 24⋅0 V and another capacitor of capacitance 6⋅0 µF is charged to 12⋅0 V. (a) Find the energy stored in each capacitor. (b) The positive plate of the first capacitor is now connected to the negative plate of the second and vice versa. Find the new charges on the capacitors. (c) Find the loss of electrostatic energy during the process. (d) Where does this energy go?

The figure shows a network of five capacitors connected to a 100 V supply. Calculate the total energy stored in the network.
Three different capacitors are·connected in series. Then:-
Capacitors connected in series have ______
The equivalent capacitance of the combination shown is:

