1000+ Electricity Fundamentals MCQ for SSC JHT [Solved]

1. What is the unit of magnetomotive force?
A. Volt
B. Tesla
C. Ampere- turn
D. Weber
Answer : C

2. How many electrons are needed in the valence orbit to give a material's stability?
A.
B.
C.
D.
Answer : A

3. If the relative permittivity of a material is 10a then its permittivity is
A. 4 × 10^7F/m
B. 4 × 10^-6 F/m
C. 8.854× 10^-11 F/m
D. 8.854 × 10^-12 F/m
Answer : C

4. The temperature coefficient of resistance of semiconductors is
A. positive
B. zero
C. negative
D. infinite
Answer : C

5. The process by which an emf and hence current is generated or induced in a conductor when there is a change in the magnetic flux linking the conductor is called
A. Electromagnetic induction
B. Mutual induction
C. Faraday's law
D. Electromagnetic interference
Answer : A

6. If the solenoid is gripped by the right hand with the fingers pointing the direction of current flowa the outstretched thumb will then point the north pole. This is known as
A. Right hand rule
B. Helix rule
C. End rule
D. Cork screw rule
Answer : B

7. The ability of a material to conduct magnetic flux through it.
A. Permittivity
B. Reluctivity
C. Conductivity
D. Permeability
Answer : D

8. The electrons in the last orbit of an atom are called _______ electrons.
A. free
B. valence
C. bound
D. thermionic
Answer : B

9. If on looking at any one end of a solenoid; the direction of current flow is found to be clockwise then the end under observation is a south pole. This is known as
A. Right hand rule
B. Left hand rule
C. Cork screw rule
D. End Rule
Answer : D

10. The phenomenon by which a magnetic substance becomes a magnet when it is place near a magnet
A. Magnetic effect
B. Magnetic phenomenon
C. Magnetic induction
D. Electromagnetic induction
Answer : C

11. One weber of flux is equal to _______ magnetic lines of force.
A. 10^6
B. 10^10
C. 4 × 10^7
D. 10^8
Answer : D

12. What is the main advantage of temporary magnets?
A. The magnetic flux can be changed.
B. Hysteresis can be decreased.
C. Magnetic materials can be used.
D. Abundance of ferromagnetic material that can be temporarily magnetized.
Answer : A

13. A negative ion results when an atom gains an additional
A. Electron
B. Proton
C. Neutron
D. Atom
Answer : A

14. The emf induced in a coil due to the change of its own flux linked with it is called
A. Mutually induced emf
B. Dynamically induced emf
C. Statically induced emf
D. Self induced emf
Answer : D

15. One that has magnetic poles produced by internal atomic structure with no external current necessary
A. Diamagnetic
B. Permanent magnets
C. Paramagnetic
D. Electromagnetic
Answer : B

16. Magnetic fields do not interact with
A. Moving permanent magnets
B. Stationary permanent magnets
C. Moving electric charges
D. Stationary electric charges
Answer : D

17. The resistance of a material is ____________ its area of cross-section.
A. directly proportional
B. independent of
C. inversely proportional to
D. equal to
Answer : C

18. One electron volt (1 eV) is equivalent to _____ joules
A. 1.3 x 10^-19
B. 1.4 x 10^-19
C. 1.5 x 10^-19
D. 1.6 x 10^-19
Answer : D

19. The temperature coefficient of resistance of a conductor ______ with an increase in temperature.
A. increases
B. decreases
C. remains the same
D. becomes negative
Answer : B

20. What is used as the insulating material or dielectric in an electric ion
A. Oiled paper
B. Mica
C. Paraffin
D. Tit anate compound
Answer : B

21. The electric flux density is a ________ quantity.
A. phasor
B. vector
C. scalar
D. variable
Answer : B

22. Calculate the flux density that will be produced by the field intensity of 2000 a. t/m for a permeability of 126 x 10^-6 T/A.t/m
A. 0.252 G
B. 0.252 x 10^-2 T
C. 0.252 T
D. 0.252 x 10^-2 G
Answer : C

23. Mmf in a magnetic circuit corresponds to _____ in an electric circuit
A. Emf
B. Voltage drop
C. Electric Field Intensity
D. Potential gradient
Answer : A

24. When the current flowsa the magnetic field ��. conductor is in what direction?
A. The same as the current direction
B. Opposite the current direction
C. Omnidirectional
D. In the direction determined by the left hand rule
Answer : D

25. Whenever a flux inking a coil or current changesa an emf is induced in it. This is known as
A. Joule's Law
B. Coulomb's Law
C. Faraday's first law of electromagnetic induction
D. Faraday's second law of electromagnetic induction
Answer : C

26. Which of the following statements is TRUE?
A. Silicon dioxide is a good
B. The current carriers in conductors are valence electrons
C. For conductorsa the valence electron are strongly attracted to the nucleus
D. The valence electrons are located in the nucleus of an atom
Answer : B

27. A principle that states that only two electrons with different spins are allowed to exist in a given orbit
A. Bohr's principle
B. Pauli exclusion principle
C. Avogadro's principle
D. Coulomb's principle
Answer : B

28. One ampere- turn is equivalent to _____ gilberts
A.
B.
C.
D.
Answer : B

29. Which of the following has the highest permeability?
A. Soft iron
B. Steel
C. Air
D. Permalloy
Answer : D

30. The idea of preventing one component from affecting another through their common electric and magnetic field is referred to as
A. Hall effect
B. Grounding
C. Shielding
D. Limiting
Answer : C

31. The permeability of permalloy is
A. Very much greater than permeability of air
B. Slightly greater than permeability of air
C. Slightly less than permeability of air
D. Equal to the permeability of air
Answer : A

32. A good conductor has how many valence electrons?
A.
B.
C.
D.
Answer : B

33. Permeance of a magnetic circuit is _________ the cross-sectional area of the circuit.
A. directly proportional to
B. inversely proportional to
C. dependent of
D. independent of
Answer : A

34. The science of adapting electronics to aerospace flight.
A. Avionics
B. Aerotronics
C. Aerodynamics
D. Astrionics
Answer : D

35. The magnetic energy stored in an inductor is ______ current.
A. Directly proportional to
B. Inversely proportional to
C. Directly proportional to the square of
D. Inversely proportional to the square of
Answer : C

36. The mass of proton is __________ the mass of an electron.
A. equal to
B. about 1837 times
C. less than
D. 200 tim es
Answer : B

37. There are how many compounds available in nature?
A.
B.
C. 300a000
D. Unlimited
Answer : D

38. The temperature coefficient of resistance of conductors is
A. positive
B. zero
C. negative
D. infinite
Answer : A

39. The emf induced in a coil due to the changing current of another neighboring coil is called
A. Mutually induced emf
B. Self induced emf
C. Statically induced emf
D. Dynamically induced emf
Answer : A

40. Back emf refers to the
A. Current equal to the applied emf
B. Opposing emf
C. Current opposing the applied emf
D. Voltage opposing the applied emf
Answer : D

41. A 6- V battery is connected across a solenoid of 100 turns having a resistance of 2 ?a Calculate the number of ampere turns?
A.
B.
C.
D.
Answer : C

42. A factor used to correct for the electrostatic forces of the more distant ions in an ionic solid.
A. Avogadro's number
B. Planck's constant
C. Boltzmann's constant
D. Madelung constant
Answer : D

43. The induced emf in a wire loop that is moved parallel to a uniform magnetic field is
A. Zero
B. Dependent on the area of the loop
C. Dependent on the shape of the loop
D. Dependent on the magnitude of the field
Answer : A

44. The energy stored in an electrostatic field or electromagnetic field is called
A. Electromagnetic energy
B. Kinetic energy
C. Potential energy
D. R est energy
Answer : C

45. If you hold the conductor with right hand so that the stretched thumb points in the direction of the currenta then encircling fingers will give the direction of magnetic lines of force round the conductor. This is known as
A. Left hand cork screw rule
B. Right hand cork screw rule
C. Left hand rule
D. Right hand rule
Answer : D

46. One oersted (Oe) is equivalent to _____ Gb/cm.
A.
B.
C.
D.
Answer : A

47. Hysteresis is a phenomenon of _________ in a magnetic circuit.
A. setting up constant flux
B. lagging of H behind B
C. lagging B behind H
D. leading B ahead H
Answer : C

48. Permanent magnets can be found in
A. electric bells
B. earphones
C. relays
D. dy namic loudspeakers
Answer : B

49. A law establishing the fact that the algebraic su of the rises and drops of the mmf around a closed loop of a magnetic circuit is equal to zero.
A. Kirchhoff's circuital law
B. Maxwell's circuital law
C. Ampere's circuital law
D. Coulomb's circuital law
Answer : C

50. Which of the following is a paramagnetic material?
A. Carbon
B. Bismuth
C. Copper
D. Oxygen
Answer : D