Electric potential and capacitance practice · Medium

The mean free path of electrons in a metal is $4 \times {10^{ - 8}}m.$ The electric field which can give on an average $2\;eV$ energy to an electron in the metal will be in units of $V/m$

A closed solid conductor of irregular shape is given some charge. Which of the following statement is correct?

The plates of a charged condenser is connected to a voltmeter. If the plates are moved apart, the reading of voltmeter will

A charge of $Q\;\mathrm{ }coulomb$ is placed on a solid piece of metal irregular shape. The charge will distribute itself

Work done in carrying a charge around an equipotential surface will

In an electric field $\mathbf{E}$, the torque acting on a dipole moment $\mathbf{p}$ is

Potential and potential gradient is a:

If the force exerted by an electric dipole on a charge q at a distance of 1 m is F, the force at a point 2 m away in the same direction will be

Assertion (A): Two capacitor of same capacity are connected first in parallel and then in series. The ratio of resultant capacities in the two cased will be $4: 1.$

Reason (R): In parallel, capacity increases and in series capacity decreases.

If the charge on a capacitor is doubled, the value of its capacitance $C$ will be

Assertion:- A parallel plate capacitor is connected across a battery through a key. A dielectric slab of dielectric constant $K$ is introduced between the plates. The energy which is stored becomes $K$ times.
Reason:- The potential difference between the plates remains constant or unchanged.

If there are $n$ capacitors in parallel connected to $V\;volt$ source, then the energy stored is equal to

If a charged spherical conductor of radius $10cm$ has potential $V$ at a point distant $5\;cm$ from its centre, then the potential at a point distant $15\;cm$ from the centre will be

Assertion:- When charges are shared between two parallel plate capacitors, charge of system is conserved but some energy is lost.
Reason:- During the sharing of charges, some energy is dissipated as heat.

Assertion: A parallel plate capacitor is connected across battery through a key. A dielectric slab of dielectric constant ${k}$ is introduced between the plates. The energy stored becomes ${k}$ times.
Reason: The surface density of charge on the plate remains constant.

$ABC$ is an equilateral triangle of side $2m$. If $\overrightarrow E = 10\,\,N{C^{ - 1}}$ then ${V_A} - {V_B}$ is

Torque acting on an electric dipole in a uniform electric field is maximum if the angle between p and E is

The capacitance of an air capacitor is $15\mu F$ the separation between the parallel plates is $6mm.$ A copper plate of $3mm$ thickness is introduced symmetrically between the plates. The capacitance now becomes

A soap bubble is given a negative charge, then its radius

Three capacitors of capacity ${C_1},{C_2},{C_3}$ are connected in series. Their total capacity will be

Identify the WRONG statement

Which among the following represents the expression of displacement current during charging of a capacitor? (Symbols have their usual meaning)

The work done in carrying a charge of $5\mu C$ from a point $A$ to a point $B$ in an electric field is $10mJ$. The potential difference $\left( {{V_B} - {V_A}} \right)$ is then

The plates of a parallel plate condenser are pulled apart with a velocity $v.$ If at any instant their mutual distance of separation is $d,$ then the magnitude of the time of rate of change of capacity depends on $d$ as follows

Considering a group of positive charges, which of the following statements is correct?

The capacity of parallel plate condenser depends on

The potential at a point due to an electric dipole will be maximum and minimum when the angles between the axis of the dipole and the line joining the point to the dipole are respectively

The intensity of electric field at a point between the plates of a charged capacitor

$0.2F$ capacitor is charged to $600\;V$ by a battery. On removing the battery, it is connected with another parallel plate condenser of $1F.$ The potential decreases to

Capacitance $\left( {\mathrm{in\;}F} \right)$ of a spherical conductor with radius $1\;m$ is