7
MCQ (Single Correct Answer)
A hemisphere is uniformely charged positively. The electric field at a point on a diameter away from the centre is directed
A
perpendicular to the diameter
B
parallel to the diameter
C
at an angle tilted towards the diameter
D
at an angle tilted away from the diameter
8
MCQ (Multiple Correct Answer)
If $\int_S \mathbf{E} . \mathrm{dS}=0$ 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
9
MCQ (Multiple Correct Answer)
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
10
MCQ (Multiple Correct Answer)
If there were only one type of charge in the universe, then
A
$\oint_s \mathbf{E} . \mathrm{dS} \neq 0$ on any surface
B
$\oint_s \mathbf{E} \cdot \mathbf{d S}=0$ if the charge is outside the surface
C
$\oint_s \mathbf{E} \mathbf{d S}$ could not be defined
D
$\boldsymbol{\oint}_s \mathbf{E} \mathbf{d S}=\frac{q}{\varepsilon_0}$ if charges of magnitude $q$ were inside the surface
11
MCQ (Multiple Correct Answer)
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 $\propto \frac{1}{r_3}$, 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