SCERT Maharashtra solutions for Physics [English] 12 Standard HSC chapter 8 - Electrostatics [Latest edition]

A metal foil of negligible thickness is introduced between two plates of a capacitor at the centre. The capacitance of the capacitor will be ______  

Capacitance (in F) of a spherical conductor of radius 1m is ______ 

A dipole is placed in a uniform electric field, its potential energy will be minimum when the angle between its axis and field is ______ 

If an electron is brought towards another electron, the electric potential energy of the system ______.

The work done in carrying a charge Q once round a circle of radius r with charge q at the centre of the circle is ______ 

You are given a number of capacitors labelled as 8μF - 250V. Find the number of capacitors needed to get an arrangement equivalent to 16μF - 1000V. 

A parallel plate capacitor with oil between the plates (dielectric constant of oil, k = 2) has a capacitance C. If the oil is removed, then the capacitance of the capacitor becomes ______ 

What do you mean by dielectric polarization?

Which physical quantity has its unit as J/C? Is it a scalar or vector?

What are linear isotropic dielectrics?

What happens to the energy stored in a capacitor, if the plates of a charged capacitor are drawn apart, the battery remaining connected?

The mean free path of electrons in a metal is 4 x 10^-8m. Find the electric field, in units of V/m, which can give on an average 2 eV energy to an electron in the metal.  

Find the electric potential at the surface of an atomic nucleus (Z = 50) of radius 9 × 10^-13 cm.  

The capacity of a parallel plate capacitor is 10 μF when the distance between its plates is 9 cm. What will be its capacity if the distance between the plates is reduced by 6 cm.

Explain the principle of a capacitor.

Obtain an expression for the electric field intensity at a point outside uniformly charged infinite plane sheet.

What is polar dielectrics? 

What is nonpolar dielectric? 

Two capacitors each of capacity 2 μF are connected in parallel. This system is connected in series with the third capacitor of 12μF capacity. Find the equivalent capacity of the system.  

Two spheres A and B of radius a and b respectively are at the same potential. Find the ratio of the surface charge densities of A and B.

A molecule with a dipole moment p is placed in an electric field of strength E. Initially the dipole is aligned parallel to the field. If the dipole is to be rotated to be anti-parallel to the field, find the work required to be done by an external agent. 

Derive an expression for the effective capacitance of three parallel plate capacitors connected in series.

Obtain an expression for the energy stored in a charged condenser. Express it in different forms. 

Obtain an expression for the capacitance of a parallel plate capacitor without a dielectric. 

Two parallel plate capacitors X and Y have the same area of the plates and the same separation between them is connected in series to a battery of 15 V. X has air between the plates while Y contains a dielectric of constant k = 2.

i) Calculate the capacitance of each capacitor if the equivalent capacitance of the combination is 2 μF.

ii) Calculate the potential difference between the plates of X and Y.

iii) What is the ratio of the electrostatic energy stored in X and Y?  

Find the amount of work done in rotating an electric dipole of dipole moment 3.2 x 10^{- 8}Cm from its position of stable equilibrium to the position of unstable equilibrium in a uniform electric field if intensity 10⁴ N/C.  

Three-point charges +q, +2q and Q are placed at the three vertices of an equilateral triangle. Find the value of charge Q (in terms of q), so that the electric potential energy of the system is zero. 

Obtain an expression for the potential energy of a dipole in an external field.

Find the capacitance of a parallel plate capacitor with a dielectric slab between the plates. 

Derive an expression for the electric potential due to an electric dipole.