The plates of a parallel plate capacitor of c | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) Initial capacitance $C = 50\,\mu F = 50 	imes 10^{-6}\,F$ and initial potential $V = 100\;V$.Initial charge $Q = CV = 50 	imes 10^{-6} 	imes 10

Vedclass · Accepted Answer

$25 	imes 10^{-2}\,J$

Vedclass · Answer

(A) Initial capacitance $C = 50\,\mu F = 50 	imes 10^{-6}\,F$ and initial potential $V = 100\;V$.Initial charge $Q = CV = 50 	imes 10^{-6} 	imes 100 = 5 	imes 10^{-3}\,C$.Since the capacitor is disconnected from the battery,the charge $Q$ remains constant.When the distance between the plates is doubled,the new capacitance $C' = C/2 = 25\,\mu F$.The new potential $V' = Q/C' = Q/(C/2) = 2V = 200\;V$.The work done by the external agent is the change in stored energy: $W = U_f - U_i$.$U_i = \frac{1}{2}CV^2 = \frac{1}{2} 	imes 50 	imes 10^{-6} 	imes (100)^2 = 0.25\;J$.$U_f = \frac{1}{2}C'V'^2 = \frac{1}{2} 	imes (C/2) 	imes (2V)^2 = \frac{1}{2} 	imes (C/2) 	imes 4V^2 = CV^2 = 0.50\;J$.$W = 0.50 - 0.25 = 0.25\;J = 25 	imes 10^{-2}\,J$.

The plates of a parallel plate capacitor of capacity $50\,\mu F$ are charged to a potential of $100\;V$ and then disconnected from the battery. The distance between the plates is then doubled. How much work is done in doing so?

Similar Questions

$A$ parallel plate air capacitor is charged to a potential difference of $V \text{ volts}$. After disconnecting the charging battery,the distance between the plates of the capacitor is increased using an insulating handle. As a result,the potential difference between the plates

In the diagram,the area of each plate is $A = 2 \,m^2$ and $d = 2 \times 10^{-3} \,m$. An electric charge of $q = 8.85 \times 10^{-8} \,C$ is given to the plate '$Q$'. Plates '$P$' and '$R$' are connected to the ground. Then the potential of plate '$Q$' is:

The capacity of a parallel plate capacitor is $C$. What will be its capacity when the separation between the plates is halved?

$A$ capacitor is connected to a battery. What happens to the force of attraction between the plates when the separation between them is halved?

The force of attraction between the plates of a parallel plate capacitor is

Vedclass Test Series

Exam Paper Generator

Online Exam Module