NEET Electrostatic Potential and Capacitance PYQ practice sheet

20 previous-year NEET Physics questions from Electrostatic Potential and Capacitance, newest papers first. Electrostatic Potential and Capacitance carries 26 of the Physics questions in NEET 2020 to 2026, so this is a good place to test yourself after revising the chapter. Marking: +4 correct, −1 wrong.

1. 1.

   RE-NEET 2026

   Three identical capacitors, $P$, $Q$ and $S$, each of the capacitance $C$, are connected to a battery of voltage $V$, as shown in the figure. If the energy stored in the capacitor $P$ and total energy stored in the system are $U_P$ and $U_T$, respectively, then the ratio $\frac{U_P}{U_T}$ is: Figure: capacitors $P$ and $Q$ are in series with each other on one branch; this branch is in parallel with capacitor $S$; the whole arrangement is connected across the battery $V$.

   • (A)
     $1/3$
   • (B)
     $1/2$
   • (C)
     $2/3$
   • (D)
     $1/6$
2. 2.

   RE-NEET 2026

   A unit positive point charge is taken slowly through an infinitesimally thin tube that is inside a charged dielectric sphere of radius $R$, having uniform positive charge density $\rho$, as shown in the figure. The initial and final positions of the charge are marked by $A$ and $B$ at distance $2R$ and $3R$ respectively, from the centre of the sphere. In this process, the magnitude of the total work done on the point charge is $\frac{\rho R^2}{n\varepsilon_0}$. The value of $n$ is : ($\varepsilon_0$ is the permittivity of vacuum) Figure: a sphere of radius $R$ with centre $O$ and uniform charge density $\rho$. $A$ is at distance $2R$ and $B$ at distance $3R$ from $O$, on different sides. A thin tube runs from $A$ to $B$ through the sphere, along which the charge is moved.

   • (A)
     $6$
   • (B)
     $2$
   • (C)
     $18$
   • (D)
     $9$
3. 3.

   RE-NEET 2026

   A point charge $Q$ is placed inside a cavity within a solid isolated conducting sphere. Consider points $A$, $B$ and $C$ as shown in the figure, where the magnitudes of the electric fields are $E_A$, $E_B$, $E_C$, respectively. The points $B$ and $C$ are at the same distance from the center of the solid sphere. The correct option is : Figure: a solid isolated conducting sphere with a small off-centre cavity containing the point charge $Q$. Point $A$ is inside the cavity near $Q$; $B$ and $C$ are outside the sphere on opposite sides, at equal distances from its centre.

   • (A)
     $E_A \neq 0,\; E_B = E_C$
   • (B)
     $E_A = 0,\; E_B > E_C$
   • (C)
     $E_A = 0,\; E_B = E_C$
   • (D)
     $E_A \neq 0,\; E_B < E_C$
4. 4.

   RE-NEET 2026

   Consider a fixed uniformly charged insulating sphere with radius $R$ and total charge $+Q$. A point charge $-q$ ($q \ll Q$) with mass $m$ is released from rest at a distance of $3R$ from the centre of the charged sphere. When the point charge reaches the surface of the sphere, its speed is: ($\varepsilon_0$ is the permittivity of vacuum, neglect gravitational forces).

   • (A)
     $\sqrt{\frac{3Qq}{4\pi\varepsilon_0 mR}}$
   • (B)
     $\sqrt{\frac{Qq}{4\pi\varepsilon_0 mR}}$
   • (C)
     $\sqrt{\frac{Qq}{3\pi\varepsilon_0 mR}}$
   • (D)
     $\sqrt{\frac{2Qq}{3\pi\varepsilon_0 mR}}$
5. 5.

   NEET 2026

   Five capacitors of capacitances $C_1=C_2=C_3=C_4=10\ \mu\text{F}$ and $C_5=2.5\ \mu\text{F}$ are connected as shown, along with a battery of 50 V. $C_2$ and $C_3$ lie on the top wire, $C_1$ is on the left side and $C_4$ on the right side, so $C_1$, $C_2$, $C_3$, $C_4$ are in a single series chain. $C_5$ is connected across the same two nodes, in parallel with this chain, and the 50 V battery is connected across the whole combination. The equivalent capacitance and the charges on each capacitor respectively are:

   • (A)
     $4\ \mu$F, $250\ \mu$C on $C_1$ to $C_4$ and $125\ \mu$C on $C_5$
   • (B)
     $5\ \mu$F, $125\ \mu$C on all capacitors
   • (C)
     $5\ \mu$F, $125\ \mu$C on $C_1$ to $C_4$ and $25\ \mu$C on $C_5$
   • (D)
     $5\ \mu$F, $250\ \mu$C on all capacitors
6. 6.

   NEET 2026

   Consider two uncharged capacitors of equal capacitance 200 pF. One of them is charged by a 100 V supply and disconnected. Now this capacitor is connected to the uncharged capacitor. The amount of electrostatic energy lost in the process is:

   • (A)
     0.5 J
   • (B)
     $1.0\times10^{-6}$ J
   • (C)
     $0.5\times10^{-6}$ J
   • (D)
     1.0 J
7. 7.

   NEET 2026

   Which of the following statements are correct? A. Inside a conductor, the electrostatic field is zero. B. Electric field at the surface of a charged conductor does not depend on its surface charge density. C. The interior of a charged conductor can have no excess charge in the static situation. D. At the surface of a charged conductor, the electrostatic field must be normal to the surface at every point. E. The electrostatic potential is zero everywhere inside a charged conductor. Choose the correct answer from the options given below:

   • (A)
     A, C and D only
   • (B)
     A, C and E only
   • (C)
     C, D and E only
   • (D)
     A, B and D only
8. 8.

   NEET 2024

   In the following circuit, the equivalent capacitance between terminal $A$ and terminal $B$ is: Four capacitors of $2\,\mu\text{F}$ each form a bridge: the upper arm has two $2\,\mu$F capacitors in series, the lower arm has two $2\,\mu$F capacitors in series, and a fifth capacitor joins the mid-points of the two arms. Terminals $A$ and $B$ are at the left and right ends.

   • (A)
     $4\ \mu F$
   • (B)
     $1\ \mu F$
   • (C)
     $0.5\ \mu F$
   • (D)
     $2\ \mu F$
9. 9.

   NEET 2024

   Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The potential ($V$) at any axial point, at 2 m distance ($r$) from the centre of the dipole of dipole moment vector $\vec P$ of magnitude $4\times10^{-6}$ C m, is $\pm9\times10^{3}$ V. (Take $\dfrac{1}{4\pi\epsilon_0}=9\times10^{9}$ SI units) Reason R: $V=\pm\dfrac{2P}{4\pi\epsilon_0 r^2}$, where $r$ is the distance of any axial point, situated at 2 m from the centre of the dipole. In the light of the above statements, choose the correct answer from the options given below:

   • (A)
     Both A and R are true and R is NOT the correct explanation of A.
   • (B)
     A is true but R is false.
   • (C)
     Both A and R are true and R is the correct explanation of A.
   • (D)
     A is false but R is true.
10. 10.

    NEET 2024

    A thin spherical shell is charged by some source. The potential difference between the two points $C$ and $P$ (in V) shown in the figure is: (Take $\dfrac{1}{4\pi\epsilon_0}=9\times10^{9}$ SI units) The shell has radius $R=3$ cm and charge $q=1\,\mu$C. $C$ is its centre and $P$ is a point on the shell.

    • (A)
      $0.5\times10^{5}$
    • (B)
      $3\times10^{5}$
    • (C)
      $1\times10^{5}$
    • (D)
      zero
11. 11.

    NEET 2024

    If the plates of a parallel plate capacitor connected to a battery are moved close to each other, then A. the charge stored in it, increases. B. the energy stored in it, decreases. C. its capacitance increases. D. the ratio of charge to its potential remains the same. E. the product of charge and voltage increases. Choose the most appropriate answer from the options given below:

    • (A)
      B, D and E only
    • (B)
      A, C and E only
    • (C)
      A, B and E only
    • (D)
      A, B and C only
12. 12.

    NEET 2023

    The equivalent capacitance of the system shown in the following circuit is : Circuit (described from the figure): Terminal $A$ connects to a $3\ \mu\mathrm{F}$ capacitor in series. Its other end connects to a parallel combination of two $3\ \mu\mathrm{F}$ capacitors (one on the upper branch, one on the lower branch). The parallel combination connects to terminal $B$.

    • (A)
      $9\ \mu\mathrm{F}$
    • (B)
      $2\ \mu\mathrm{F}$
    • (C)
      $3\ \mu\mathrm{F}$
    • (D)
      $6\ \mu\mathrm{F}$
13. 13.

    NEET 2023

    An electric dipole is placed as shown in the figure. Figure (described): Charges $-q$ and $+q$ lie on a horizontal line, each $3\ \mathrm{cm}$ from the midpoint $O$ ($-q$ on the left, $+q$ on the right). The point $P$ lies on the same line (axis of the dipole), on the side of $+q$, at a distance of $5\ \mathrm{cm}$ from $O$. The electric potential (in $10^2\ \mathrm{V}$) at point $P$ due to the dipole is ($\varepsilon_0$ = permittivity of free space and $\dfrac{1}{4\pi\varepsilon_0} = K$):

    • (A)
      $\left(\dfrac{8}{3}\right)qK$
    • (B)
      $\left(\dfrac{3}{8}\right)qK$
    • (C)
      $\left(\dfrac{5}{8}\right)qK$
    • (D)
      $\left(\dfrac{8}{5}\right)qK$
14. 14.

    NEET 2022

    Two hollow conducting spheres of radii $R_1$ and $R_2$ ($R_1\gg R_2$) have equal charges. The potential would be:

    • (A)
      dependent on the material property of the sphere
    • (B)
      more on the bigger sphere
    • (C)
      more on the smaller sphere
    • (D)
      equal on both the spheres
15. 15.

    NEET 2022

    The angle between the electric lines of force and the equipotential surface is:

    • (A)
      $180^{\circ}$
    • (B)
      $0^{\circ}$
    • (C)
      $45^{\circ}$
    • (D)
      $90^{\circ}$
16. 16.

    NEET 2022

    A capacitor of capacitance $C=900\ \text{pF}$ is charged fully by 100 V battery B as shown in figure (a). Then it is disconnected from the battery and connected to another uncharged capacitor of capacitance $C=900\ \text{pF}$ as shown in figure (b). The electrostatic energy stored by the system (b) is:

    • (A)
      $1.5\times10^{-6}$ J
    • (B)
      $4.5\times10^{-6}$ J
    • (C)
      $3.25\times10^{-6}$ J
    • (D)
      $2.25\times10^{-6}$ J
17. 17.

    NEET 2021

    The equivalent capacitance of the combination shown in the figure is : Figure: three identical capacitors, each of capacitance $C$, are connected between two terminals. One capacitor is in the top wire and one is in the bottom wire of a rectangular loop. The third capacitor is in a vertical branch joining the two wires. The right-hand end of both the top and the bottom wire is joined to the right terminal, while the left-hand ends of both wires are joined to the left terminal.

    • (A)
      $3C/2$
    • (B)
      $3C$
    • (C)
      $2C$
    • (D)
      $C/2$
18. 18.

    NEET 2021

    Two charged spherical conductors of radius $R_1$ and $R_2$ are connected by a wire. Then the ratio of surface charge densities of the spheres $(\sigma_1/\sigma_2)$ is :

    • (A)
      $\sqrt{\dfrac{R_1}{R_2}}$
    • (B)
      $\dfrac{R_1}{R_2}$
    • (C)
      $\dfrac{R_1^{2}}{R_2^{2}}$
    • (D)
      $\dfrac{R_2}{R_1}$
19. 19.

    NEET 2021

    A parallel plate capacitor has a uniform electric field $\vec{E}$ in the space between the plates. If the distance between the plates is $d$ and the area of each plate is $A$, the energy stored in the capacitor is : ($\varepsilon_0$ = permittivity of free space)

    • (A)
      $\dfrac{1}{2}\varepsilon_0E^{2}Ad$
    • (B)
      $\varepsilon_0EAd$
    • (C)
      $\dfrac{E^{2}Ad}{\varepsilon_0}$
    • (D)
      $\dfrac{1}{2}\varepsilon_0E^{2}$
20. 20.

    NEET 2021

    Twenty seven drops of same size are charged at $220\ \mathrm{V}$ each. They combine to form a bigger drop. Calculate the potential of the bigger drop.

    • (A)
      $1520\ \mathrm{V}$
    • (B)
      $660\ \mathrm{V}$
    • (C)
      $1980\ \mathrm{V}$
    • (D)
      $1320\ \mathrm{V}$