List of top Physics Questions on electrostatic potential and capacitance asked in NEET (UG)

An electric dipole is placed as shown in the figure.
 

The electric potential (in 102 V) at point P due to the dipole is (ε₀ = permittivity of free space and \(\frac{1}{4\pi\epsilon_0}=K\)):

A parallel plate capacitor has a uniform electric field ‘ 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 : (ε₀=permittivity of free space)

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

The total capacity of the system of capacitors shown in the adjoining figure between the points A and B is

A short electric dipole has a dipole moment of \(16 \times 10^{-9} C\, m\). The electric potential due to the dipole at a point at a distance of \(0.6 \,m\) from the centre of the dipole, situated on a line making an angle of \(60\degree\)with the dipole axis is : \((\frac {1}{4\pi \epsilon_o}= 9 \times 10^9 N\,m^2/C^2)\)

In a certain region of space with volume $0.2 \,m^3$, the electric potential is found to be $5\,V$ throughout. The magnitude of electric field in this region is:

The energy required to break one bond in DNA is $10^{-20}J $. This value in eV is nearly

The electrostatic force between the metal plate of an isolated parallel plate capacitor $C$ having charge $Q$ and area $A$, is

Suppose the charge of a proton and an electron differ slightly. One of them is –e, the other is (e +△e). If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero, then △e is of the order of [Given mass of hydrogen m_h = 1.67 × 10^–27 kg]

The ratio of wavelengths of the last line of Balmer series and the last line of Lyman series is

An arrangement of three parallel straight wires placed perpendicular to plane of paper carrying same current ‘I’ along the same direction is shown in Fig. Magnitude of force per unit length on the middle wire ‘B’ is given by

A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system :

A parallel-plate capacitor of area $A$, plate separation d and capacitance $C$ is filled with four dielectric materials having dielectric constants $k_1, k_2, k_3 $ and $ k_4$ as shown in the figure below. If a single dielectric material is to be used to have the same capacitance $C$ in this capacitor, then its dielectric constant $k$ is given by

A parallel plate air capacitor of capacitance C is connected to a cell of emf V and then disconnected from it. A dielectric slab of dielectric constant K, which can just fill the air gap of the capacitor, is now inserted in it. Which of the following is incorrect?

A parallel plate air capacitor has capacity $C$, distance of separation between plates is $d$ and potential difference $V$ is applied between the plates. Force of attraction between the plates of the parallel plate air capacitor is

If potential (in volts) in a region is expressed as $V(x, y , z)$ = $6xy - y + 2yz$, the electric field $(in\, N/C)$ at point $(1, 1, 0)$ is

The enolic form of ethyl acetoacetate as below has

Two thin dielectric slabs of dielectric constants K₁ and K₂ (K₁ < K₂) are inserted between plates of a parallel plate capacitor, as shown in the figure. The variation of electric field 'E' between the plates with distance 'd' as measured from plate P is correctly shown by:

A conducting sphere of radius $R$ is given a charge $Q$. The electric potential and the electric field at the centre of the sphere respectively are

In a region, the potential is represented by V(x, y, z) = 6x - 8xy - 8y + 6yz, where $V$ is in volts and $x, y, z$ are in metres. The electric force experienced by a charge of $2$ coulomb situated at point $(1, 1, 1)$ is

What is the flux through a cube of side a if a point charge of q is at one of its corner?

A parallel plate capacitor has a uniform electric field E in the space between the plates. If the distance between the plates is d and area of each plate is A, the eneigy stored in the capacitor is

Three charges, each $+q$, are placed a at the corners of an isosceles triangle $ABC$ of sides $BC$ and $AC$, $2a$. $D$ and $E$ are the mid points of $BC$ and $CA$. The work done in taking a charge $Q$ from $D$ to $E$ is

A series combination of $n_1$ capacitors, each of value $ C_1$, is charged by a source of potential difference $4V$. When another parallel combination of $n_2$ capacitors, each of value $C_2$, is charged by a source of potential difference $V$, it has the same (total) energy stored in it, as the first combination has. The value of $C_2$, in terms of $C_1$, is then