Physics Class 12thChapter 1 Electric Charges and Fields
1. Electric Charges and Fields (Topics in this Chapter)
Electric Charges: Conservation of charges, Coulomb's law-force between two point charges, force between multiple charges; superposition principle and continuous charge distribution.
Electric field, electric field due to a point charge, electric field lines, electric dipole, electric field due to a dipole, torque on a dipole in uniform electric field.
Electric flux, statement of Gauss's theorem and its applications to find fields due to infinitely long straight wire, uniformly charged infinite plane sheets and uniformly charged thin spherical shell (field in side and outside).
Important Questions for MPBSE PAPER for 2022
Q.01.State & prove the coulomb’s inverse square law of electrostatic charge. On the basis of define unit charge. What is the condition for the law to be applicable?
Q.02.Derive the expression for intensity of electric field at a point due to a dipole on the axial line.(Axial or end on position)
Q.03.What is an electric dipole? Derive the expression for the intensity of electric field on the equatorial position or Coaxial position(Broadside-on position) of the dipole.
Q.04.Define electric flux write its SI unit and dimensional formula.
OR
Define electric flux? How many types of flux are there?
Q.05.Write and prove the Gauss Theorem.
06.State Gauss’s theorem and derive Coulomb’s inverse square law with the help of Gauss Theorem.
Q.07.Derive the expression for the torque acting on the dipole when kept in a uniform electric field and hence define dipole moment.
Q.08.Derive the expression for the amount of work done in rotating a dipole in a uniform electric field.
Q.09.Derive an expression for the intensity of electric field due to a uniform infinite plane sheet of charge.
Q.10.Derive an expression for the intensity of electric field due to a long straight charged wire
Q.11.Prove that intensity of field is zero inside a spherical shell, while in outside it is such that all the charges are concentrated at the centre.
OR
D Derive an expression for the intensity of electric field due to a spherical shell of charge using Gauss theorem at the following points:-
(a) When the observation point P lies outside the spherical shell.
(b) When point P lies on the surface of spherical shell.
(c) When the point P lies inside the spherical shell.
Q 12 .Derive an expression for the potential energy of a dipole in an uniform electric field.
Q. 13.State unit of
Q 14.Who gave the sign + and to the charges ?
Q. 15.State relation between electric flux and electric field.
Q. 16.Write relation between permittivity of free space and permittivity of a medium ?
Q. 17.What is the force acting on charge q in an electric field E?
Q. 18.Define "unit charge”.
Q. 19.Write the basic properties of electric charge ?
Q. 20.Define intensity of electric field. Write its SI Unit.
Q. 21.Write definition of intensity of electric field. Write its SI unit.
Q. 22.What is an electric dipole ?
Q. 23.Define electric dipole moment and writ its SI unit.
Q. 24.What do you mean by quantization of electric charge ?
Q. 25.State principle of conservation of charges. Give examples.
26.(a) Define intensity of electric field. Write its unit.
(b) Write any four properties of electric lines of force. Draw the electric lines of force of an isolated charge.
