Electrostatics-10 Important basic MCQs (Quiz) Part 3
1. A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius and outer radius c is concentric with the solid sphere and has a net charge – Q. The surface charge density on the inner and outer surfaces of the spherical shell will be
(A) -\frac{2Q}{4\mathrm{πb}^2},\;\frac Q{4\mathrm\pi\;\mathrm c^2}
(B) -\frac{Q}{4\mathrm{πb}^2},\;\frac Q{4\mathrm\pi\;\mathrm c^2}
(C) 0, \frac Q{4\mathrm\pi\;\mathrm c^2}
(D) None of the above
2. A metallic solid sphere is placed in a uniform electric field. The lines of force follow the path(s) shown in figure as:
(A) 1
(B) 2
(C) 3
(D) 4
3.An uncharged sphere of metal is placed in between two charged plates as shown. The lines of force look like
(A) A
(B) B
(C) C
(D) D
4.Figures below show regular hexagons, with charges at the vertices. In which of the following cases the electric field at the centre is not zero
(A) 1
(B) 2
(C) 3
(D) 4
5. Two point charges +8q and -2q are located at x=0 and x=L respectively. The location of a point on the x-axis at which the net electric field due to these two point charges is zero is
(A) 8 L
(B) 4 L
(C) 2 L
(D) \frac L4
6. At a certain distance from a point charge the electric field is 500 V/m and the potential is 3000V/m . What is this distance
(A) 6m
(B) 12m
(C) 36m
(D) 144m
7. The figure shows some of the electric field lines corresponding to an electric field. The figure suggests
(A)E_A>\;E_B>\;E_C
(B) E_A=\;E_B=\;E_C
(C) E_A=\;E_C>\;E_B
(D) E_A=\;E_C<\;E_B
8. Point charges +4q, -q and +4q are kept on the axis at points x=0, x=a and x=2a respectively, then
(A) Only ‘-q’ is in stable equilibrium
(B) None of the charges are in equilibrium
(C) All the charges are in unstable equilibrium
(D) All the charges are in stable equilibrium
9. Two point charges of 20\;\mu C\; and 80\;\mu C\; are 10 cm apart. Where will the electric field strength be zero on the line joining the charges from 20\;\mu C\; charge
(A) 0.1 m
(B)0.033 m
(C) 0.33 m
(D) 0.04 m
10. What is the magnitude of a point charge which produces an electric field of 2 N/coulomb at a distance of 60 cm
(A) 8\;\times\;10^{-11}\;C
(B) 2\;\times\;10^{-12}\;C
(C) 3\;\times\;10^{-11}\;C
(D) 6\;\times\;10^{-10}\;C