Q: A capacitor of capacitance C is charged to a potential V. The flux of the electric field through a closed surface enclosing the positive plate of the capacitor is:

From the Gauss's law aligned & = q _ in _0 = Q _0 Q = CV \\ & = CV _0 aligned

Question 1

A parallel plate capacitor with plate area A and plate separation d=2 ~m has a capacitance of 4 ~F . The new capacitance of the system if half of the space between them is filled with a dielectric mat

Accepted Answer

We have, C_i= A _0 d =4 F C_f= A _0 d-t+ t k = A _0 d- d 2 + d 2 3 = A _0 d (1- 1 2 + 1 6 ) = 4 F 2 3 =6 F

Question 2

A capacitor of capacitance C is charged to a potential V. The flux of the electric field through a closed surface enclosing the positive plate of the capacitor is:

Accepted Answer

From the Gauss's law aligned & = q _ in _0 = Q _0 Q = CV \ & = CV _0 aligned

Question 3

The work done in placing a charge of 8 10^ -18 coulomb on a condenser of capacity 100 microfarad is

Accepted Answer

Work done = 1 2 q ^2 C = (8 10^ -18 )^2 2 100 10^ -6 =32 10^ -32 ~J

Question 4

In a given network the equivalent capacitance between A and B is C_ 1 =C_ 4 =1 F, C_ 2 =C_ 3 =2 F.

Accepted Answer

The equivalent circuit is shown in figure. C _ AB =1+ 2 2 2+2 +1 C _ AB =3 F

Capacitance — Previous Year Questions & Solutions