Electric Field MCQ

1. Drift velocity acquired per unit electric field applied is called as

  1. Relaxation time
  2. Current density
  3. Potential difference
  4. Electron mobility
Answer
Answer. d

2. Two infinite parallel metal plates are charged with equal surface charge density of the same polarity. The electric field in the gap between the plates is

  1. Same as that produced by one plate
  2. Half that of the field produced by one plate
  3. Zero
  4. Depends upon coordinates of field post
Answer
Answer. c

3. The electric field lines are

  1. Closed lines
  2. Smooth curved lines
  3. Either straight line or smooth curved lines
  4. Straight line
Answer
Answer. c

4. For a hollow charged thin metallic sphere with centre O and a point on the surface of sphere as, R, the magnitude of electric field and potential from O to R is respectively

  1. zero, zero
  2. zero, constant
  3. constant zero
  4. constant, constant
Answer
Answer. b

5. When a voltage is applied, the direction of electric field is always from ______ to _____

  1. Positive, negative
  2. Negative, positive
  3. North, south
  4. West, east
Answer
Answer. a

6. Electric field intensity is a quantity of

  1. Scalar
  2. Vector
  3. Both (a) and (b)
  4. None of the above
Answer
Answer. b

7. A field and equipotential surface are

  1. Always parallel
  2. Always at 90°
  3. Inclined at any angle
  4. Both (a) and (c)
Answer
Answer. b

8. The total number of lines of force emanating from certain charge is called as?

  1. Electric intensity
  2. Electric field strength
  3. Electric lines of forces
  4. Electric flux
Answer
Answer. d

9. Electric field is defined as the electric force per unit

  1. Length
  2. Charge
  3. Flux
  4. Momentum
Answer
Answer. b

10. An Electric field deflects beams of

  1. Protons
  2. Electrons
  3. Neutrons
  4. Both protons and electrons
Answer
Answer. d

11. A hollow sphere of charge does not produce an electric field at

  1. Interior point
  2. Outer point
  3. Beyond 2 meters
  4. None of the above
Answer
Answer. a

12. Electric field is defined as

  1. Potential per unit distance
  2. Force per unit charge
  3. Voltage per unit current
  4. None of these
Answer
Answer. b

13. Electric field is a

  1. Scalar quantity
  2. Vector quantity
  3. Both scalar quantity and vector quantity
  4. None of these
Answer
Answer. b

14. The electric displacement is in the direction of electric field intensity E if the medium is

  1. Homogeneous and isotropic
  2. Non homogeneous and anisotropic
  3. Non homogeneous and isotropic
  4. Homogeneous and anisotropic
Answer
Answer. a

15. The electric field intensity inside a charged spherical conductor is

  1. Zero
  2. Constant
  3. Infinite
  4. None of the other options
Answer
Answer. a

16. Which of the following is a scalar quantity?

  1. Electric field strength
  2. Electric displacement density
  3. Electric potential
  4. Force
Answer
Answer. c

17. What does the region around the stationary electric charge has?

  1. Electric field
  2. Magnetic field
  3. Semi permeable region
  4. Insulating field
Answer
Answer. a

18. The electric field strength a distance point, due to a point charge, +q, located at the origin is 100 μVm. If the point is now enclosed by a perfectly conducting sheet sphere at the point P. Outside the sphere, becomes

  1. 0 μVm
  2. 100 μVm
  3. -100 μVm
  4. 50 μVm
Answer
Answer. a

19. A solid sphere made of insulating material has a radius R and has a total charge Q distributed uniformly in its volume. What is the magnitude of the electric field intensity E, at a distance r (0 < r < R) inside the sphere?

  1. $\frac{Qr}{4 \pi \epsilon_{o}R^{3}}$
  2. $\frac{3Qr}{4 \pi \epsilon_{o}R^{3}}$
  3. $\frac{QR}{4 \pi \epsilon_{o}r^{3}}$
  4. $\frac{Q}{4 \pi \epsilon_{o}r^{2}}$
Answer
Answer. a

20. An electric field of 100kV/m is equal to

  1. 100 V/m
  2. 100 mV/mm
  3. 100 V/mm
  4. 100 meV/μm
Answer
Answer. c

21. The lines of force due to charged particles are

  1. Always straight
  2. Always curved
  3. Sometimes curved
  4. None of these
Answer
Answer. b

22. The electric flux and field intensity inside a conducting sphere is

  1. Zero
  2. Maximum
  3. Uniform
  4. Minimum
Answer
Answer. a

23. Midway between two equal and similar charges, a third equal and similar charge is placed. Then this third charge will

  1. Remain in stable equilibrium
  2. Be in unstable equilibrium
  3. Not be in equilibrium
  4. Will move out of the field to influence the two charges
Answer
Answer. a

24. Inside a hollow conducting sphere, electric field

  1. is zero
  2. is a non-zero constant
  3. changes with the magnitude of the charge given to the conductor
  4. changes with distance from the centre of the sphere
Answer
Answer. a

25. Electric field intensity at any point is equal to

  1. Potential gradient at that point
  2. Potential at that point
  3. Potential difference at that point
  4. Work done at that point
Answer
Answer. a