Electric Charge...

A point charge + q is placed at a distance d from an isolated conducting plane. The field at a point P on the other side of the plane is

A hemisphere is uniformly charged positively. The electric field at a point on a diameter away from the centre is directed

If \(\int\limits_sE.dS=0\) over a surface, then

(a) the electric field inside the surface and on it is zero

(b) the electric field inside the surface is necessarily uniform

(c) the number of flux lines entering the surface must be equal to the number of flux lines leaving it

(d) all charges must necessarily be outside the surface

The electric field at a point is

(a) always continuous

(b) continuous if there is no charge at that point

(c) discontinuous only if there is a negative charge at that point

(d) discontinuous if there is a charge at that point

If there were only one type of charge in the universe, then

(a) \(\oint\limits_sE.dS\neq0\) on any surface

(b) \(\oint\limits_sE.dS=0\) if the charge is outside the surface

(c) \(\oint\limits_sE.dS\) could not be defined

(d) \(\oint\limits_sE.dS={q\over \varepsilon_0}\) if charges of magnitude q were inside the surface

Consider a region inside which there are various types of charges but the total charge is zero. At points outside the region,

(a) the electric field is necessarily zero

(b) the electric field is due to the dipole moment of the charge distribution only

(c) the dominant electric field is \(\propto {1\over r^3}\), for large r, where r is the distance from a origin in this regions

(d) the work done to move a charged particle along a closed path, away from the region, will be zero