Class-XII 

1. The surface considered for Gauss’s law is called

(a) Closed surface

(b) Spherical surface

(c) Gaussian surface

(d) Plane surface

2. Which of the following statements is not true about Gauss’s law?

(a) Gauss’s law is true for any closed surface.

(b) The term q on the right side side of Gauss’s law includes the sum of all charges enclosed by the surface.

(c) Gauss’s law is not much useful in calculating electrostatic field when the system has some symmetry.

(d) Gauss’s law is based on the inverse square dependence on distance contained in the coulomb’s law

3. Electric field lines provide information about

(a) field strength

(b) direction

(c) nature of charge

(d) all of these

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

5. The SI unit of electric flux is

(a) N C-1 m-2

(b) N C m-2

(c) N C-2 m2

(d) N C-1 m2

6.If an electric dipole is kept in a uniform electric field then resultant electric force on it is :

(a) always zero

(b) never zero

(c) depend upon capacity of dipole

(d) None

7.The number of electron-taken out from a body to produce 1 coulomb of charge will be :

(a) 6.25 × 1018

(b) 625 × 1018

(c) 6.023 × 1023

(d) None

8.Coulomb’s law written as

F = kq1q2/r^2

where ε0 is the permitivity of free space. The SI units of ε0 will be:

(a) N-1m-2C-2

(b) Nm-2C2

(c) N-1m-2C9.

(d) Nm-2C2

9.The SI units of electric dipole moment are:

(a) C

(b) Cm-1

(c) Cm

(d) Nm-1

10.Quantisation of charge implies:

(a) Charge does not exist

(b) Charge exists on particles

(c) There is a minimum permissible magnitude of charge

(d) Charge can’t be created

11.The minimum amount of charge observed so far is:

(a) 1 C

(b) 4.8 × 1-13 C

(c) 1.6 × 10-19 C

(d) 1.6 × 1019 C

12. When a dipole of moment  P is placed in uniform electric field   E, then the torque acting on the dipole i

13.The conservation of electric charge implies that:

(a) Charge can’t be created

(b) Charge can’t be destroyed

(c) The number of charged particle in the universe is constant

(d) Simultaneous creation of equal and opposite charges is permissible

14. In a parallel plate capacitor, the capacity increases if

(a) area of the plate is decreased.

(b) distance between the plates increases.

(c) area of the plate is increased.

(d) dielectric constantly decreases.

15.. Two spherical conductors each of capacity C are charged to potential V and -V. These are then connected by means of a fine wire. The loss of energy is

(a) zero

(b) ½ CV2

(c) CV2

(d) 2 CV2

16.The unit of intensity of electric field is :

(a) metre/volt

(b) Joule/newton

(c) Coulomb/newton

(d) Newton/coulomb