Test: Electric Field Lines & Electric Flux(28 Oct) - JEE MCQ

Electrostatic field lines start or end only at 90⁰ to the surface of the conductor. So curve (b) cannot represent electrostatic field lines.

From the figure, it is clear that, there cannot be a neutral point between a positive and a negative charge. Neutral point can be only there between two like charges i.e„ A and C. As magnitude of charge A is smaller than the magnitude of charge C, therefore, neutral point would lie closer to the charge A.

The field lines of single negative charge are radially inward.

From the given figure it is clear that, maximum number of electric lines of force are associated with charge C, so it must have the largest magnitude.

In the given figure, the electric lines of force emanate from A and C. Therefore, charges A and C must be positive.

Electric field strength is maximum where the electric field lines are closer.

For a uniformly charged hollow cylinder, the electric field lines are as shown in figure (b).

The field lines of a single positive charge are radially outward.

In a charge-free region, electric field lines can be taken to be continuous curves without any breaks.

Electric flux = electric field intensity x area. The dimension of field intensity is [M L T^-3 I^-1] and the dimension of the area is [L²]. Therefore, the dimension of flux = [M L³ T^-3 I^-1]. This can also be justified as flux=potential x length. By putting the dimensions of potential and length, we can get the same result.