List of top Physics Questions on Electrostatics asked in JEE Main, VITEEE

Two point charges $7\mu C$ at (–9,0,0) and $–2\mu C$ at (9,0,0) are placed in an external electric field $\vec{E} = \frac{A}{r^2} \hat{r}$ where A = $10^5$ SI unit. Find potential energy of system ?

Four charges are kept as shown in the figure. Find magnitude of electric field at point P. P is mid point of line AB.

Electric potential at a point is V = Ar$^3$ + B. Find charge enclosed in a sphere of radius 1m, centered at r = 0

Three uniformly charged concentric shells are kept as shown in the diagram. Charges on individual shells are as shown. Find the final potential on each shell :

A rod has uniformly distributed charge $24\,\mu$C and length $10$ cm. Find force on $1\,\mu$C particle placed at a distance $2$ cm from one end of the rod.

(I) Gauss Law is defined for inverse square of distance forces.
(II) Work done by uniform electric field on a charge moving in a circle is zero.
(III) Electric field of a point-charge forms concentric circle around it.
(IV) Electric field lines forms closed loop.
Choose correct option(s).

(A) Equivalent capacitance is lower than the least of capacitors present in series.
(B) One method of increasing the capacitance is to decrease the distance between plates and increase cross-sectional area.
(C) Electric field inside an isolated capacitor decreases after inserting a dielectric.
(D) Displacement of charge does not happen when a dielectric is inserted in an isolated capacitor because dielectric acts like an insulator.
(E) Energy of an isolated capacitor increases when a dielectric is inserted in the capacitor.
Of the following statements, which are true?

A bulb rated 60 W operates for 2 hours. How much energy does it consume in this time?

A capacitor is charged with a voltage of 100 V. If the capacitance of the capacitor is $ 10 \, \mu\text{F} $, what is the charge on the capacitor?

An electric dipole is placed at a distance of 2 cm from an infinite plane sheet having positive charge density $ \sigma $. Choose the correct option from the following.

The battery of a mobile phone is rated as 4.2 V, 5800 mAh. How much energy is stored in it when fully charged?

Consider two infinitely large plane parallel conducting plates as shown below. The plates are uniformly charged with a surface charge density $ +\sigma $ and $ -\sigma $. The force experienced by a point charge $ +q $ placed at the mid point between the plates will be:

Three parallel plate capacitors $ C_1 $, $ C_2 $, and $ C_3 $ each of capacitance 5 µF are connected as shown in the figure. The effective capacitance between points A and B, when the space between the parallel plates of $ C_1 $ capacitor is filled with a dielectric medium having dielectric constant of 4, is:

Two metal spheres of radius $ R $ and $ 3R $ have same surface charge density $ \sigma $. If they are brought in contact and then separated, the surface charge density on smaller and bigger sphere becomes $ \sigma_1 $ and $ \sigma_2 $, respectively. The ratio $ \frac{\sigma_1}{\sigma_2} $ is:

The electrostatic potential on the surface of a uniformly charged spherical shell of radius $ R = 10 \, \text{cm} $ is 120 V. The potential at the centre of the shell, at a distance 5 cm from the centre, and at a distance 15 cm from the centre of the shell are:

For a short dipole placed at origin $ O $, the dipole moment $ P $ is along the $ x $-axis, as shown in the figure. If the electric potential and electric field at $ A $ are $ V_0 $ and $ E_0 $ respectively, then the correct combination of the electric potential and electric field, respectively, at point $ B $ on the $ y $-axis is given by:

Match List - I with List - II:

List - I:

(A) Electric field inside (distance $ r > 0 $ from center) of a uniformly charged spherical shell with surface charge density $ \sigma $, and radius $ R $.
(B) Electric field at distance $ r > 0 $ from a uniformly charged infinite plane sheet with surface charge density $ \sigma $.
(C) Electric field outside (distance $ r > 0 $ from center) of a uniformly charged spherical shell with surface charge density $ \sigma $, and radius $ R $.
(D) Electric field between two oppositely charged infinite plane parallel sheets with uniform surface charge density $ \sigma $.

List - II:

(I) $ \frac{\sigma}{\epsilon_0} $
(II) $ \frac{\sigma}{2\epsilon_0} $
(III) 0
(IV) $ \frac{\sigma}{\epsilon_0 r^2} $ Choose the correct answer from the options given below:

A point charge causes an electric flux of $ -2 \times 10^4 \, \text{Nm}^2\text{C}^{-1} $ to pass through a spherical Gaussian surface of 8.0 cm radius, centered on the charge. The value of the point charge is:

There are two charged spheres of radius $R$ and $3R$. When the spheres are made to touch each other and then separate, the surface charge density becomes $r_1$ and $r_2$ respectively. Find $\frac{r_1}{r_2}$.

Given $\lambda = \frac{2nc}{m}$ (linear charge density) for a wire which is passing through the body diagonal of a closed cube of side length $\sqrt{3}$ cm. Find the flux through the cube.

There are two charged spheres of radius $ R $ and $ 3R $. When the spheres are made to touch each other and then separate, the surface charge density becomes $ \sigma_1 $ and $ \sigma_2 $ respectively. Find the ratio $ \frac{\sigma_1}{\sigma_2} $.

Assertion (A): Work done to move a charge between two points is zero inside a uniformly charged shell.
Reason (R): Potential inside a uniformly charged shell is constant and equal to the potential at its surface.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Work done in moving a test charge between two points inside a uniformly charged spherical shell is zero, no matter which path is chosen.
Reason R: Electrostatic potential inside a uniformly charged spherical shell is constant and is same as that on the surface of the shell.
In the light of the above statements, choose the correct answer from the options given below

Electric charge is transferred to an irregular metallic disk as shown in the figure. If $ \sigma_1 $, $ \sigma_2 $, $ \sigma_3 $, and $ \sigma_4 $ are charge densities at given points, then choose the correct answer from the options given below:

An electron is released from rest near an infinite non-conducting sheet of uniform charge density '–σ'. The rate of change of de-Broglie wavelength associated with the electron varies inversely as $n^{th}$ power of time. The numerical value of $n$ is ______.