Two charges of equal magnitudes kept at a distance r exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is-

A cylinder of radius R and length L is placed in a uniform electric field E parallel to the cylinder axis. The total flux for the surface of the cylinder is given by-

Two similar spheres having +Q and -Q charges are kept at a certain distance. F force acts between the two. If at the middle of two spheres, another similar sphere having +Q charge is kept, then it experiences a force in magnitude and direction as-

A charge Q is divided into two parts of q and Q – q. If the coulomb repulsion between them when they are separated is to be maximum, the ratio of Q/q should be-

The electric field inside a spherical shell of uniform surface charge density is-

Electric field at a point varies as r° for-

An electric charge q is placed at the centre of a cube of side a. The electric flux on one of its faces will be

Total electric flux coming out of a unit positive charge kept in air is-

The electric field intensity due to an infinite cylinder of radius R and having charge q per unit length at a distance rir r(r > R) from its axis is-

A point charge q is placed at a distance a/2 directly above the centre of a square of side a. The electric flux through the square is

Which of the following graphs shows the variation of electric field E due to a hollow spherical conductor of radius R as a function of distance from the centre of the sphere?

The magnitude of electric field intensity E is such that, an electron placed in it would experience an electrical force equal to its weight is given by--

SI unit of permittivity of free space is-

A charge Q is placed at the centre of the line joining two point charges +q and +q. The ratio of charges Q and q is-

The force per unit charge is known as-

Electric field lines provide information about-

Which of the following figures represent the electric field lines due to a single negative charge?

The SI unit of electric flux is-

The unit of electric dipole moment is-