PHYSICS MCQS FOR COMPETITIVE EXAMS PHYSICS MCQS PHYSICS MCQS FOR MATRIC PHYSICS MCQS FOR FSC PHYSICS MCQS FOR TEST PREPARATION

 

PHYSICS MCQS FOR COMPETITIVE EXAMS 

                  PHYSICS MCQS     

 PHYSICS MCQS FOR MATRIC     

  PHYSICS MCQS FOR FSC  

PHYSICS MCQS FOR PREPARATION

 PHYSICS MCQS 

 

UNITS, DIMENSIONS AND VECTORS

ANSWERS ARE AT THE END

1. The fundamental unit of length in SI

system is

(a) meter         (b) foot

(c) mile            (d) yard

2. The SI unit of capacitance is

(a) Henry             (b) Farad

(c) Ohm              (d) Lux

3. Which of the following is not SI base unit?

(a) kilogram              (Ampere                                                   

 (c) mole                    (d) Rutherford

4. Curie is the unit of

(a) luminous intensity             (b) radioactivity

(c) amount of substance         (d) electric current

5. Which of the following is not a unit of   radioactivity?

(a) Curie                    (b) Becquerel

(c) Rutherford         (d) Candela

6. The SI derived unit of magnetic flux is

(a) Lumen        (b) Tesla

(c) Henry          (d) Weber

7. Lux is the SI unit of

(a) luminous flux
(b) illuminance
(c) magnetic flux
(d) inductance

8. Candela is the SI base unit of

(a) luminance                         (b) luminous flux

(c) luminous intensity          (d) radiant intensity

9. Candela per square is the SI unit of

(a) luminous flux            (b) luminous intensity

(c) luminance

10. The SI unit of magnetic flux density is

(a) Tesla           (b) Henry

(c) Weber         (d) Ohm

11. In CGS system, the unit of magnetic field intensity is

(a) Oersted      (b) Ampere per meter

(c) Ampere       (d) Farad

 

12. The SI unit of solid angle is

(a) steradian    (b) radian     (c) degree       (d) Joule

13. Which of the following is not a unit of plane angle?

a)  degree        b)   radian

c)  gradian       c)  steradian

 

14. A dimensionless quantity is a quantity
without an associated physical
dimension. Which of the following is
not a dimensionless quantity?

(a) radian
(b) π (pi)
(c) decibel
(d) force

15. Generally one house power (HP) is equal to how many watts?

(a) 546 W         (b) 646 W

(c) 746 W          (d) 846 W

16. In SI system, volt per meter is the unit of

(a) electric filed strength        (b) magnetic field strength

(c) magnetic flux density        (d) magnetic flux

17. In SI system, Ohm is the unit of

(a) electrical  conductance       (b) electrical resistance

(c) inductance                            (d) capacitance

18. A light-year is a unit of

(a) mass                       (b) time

(c) temperature         (d) length

19. Which of the following is not a unit of length?

(a) micron             (b)yard                                              

(c) inch             (d) Kelvin

20. One micron is equivalent to

(a)10^-2 m         (b) 10^-4 m

(c) 10^-6 m        (d) 10^-8 m

21. The Pascal is not the SI derived unit
of

(a) pressure
(b) stress
(c) tensile strength
(d) work

 

22. Which of the following does not have the same dimensions?

(a) energy, work, heat      (b) pressure, stress, young’s modulus

(c) voltage, electromotive force, potential difference

(d) electric flux, electric field, electric dipole moment

23. The dimensions of force are

(a) MLT^-2                (b) ML^2T^-2

(c) M^2L^2T^-2       (d) ML^2T^-1

24. The dimensions of torque are

(a) MLT^-1              (b) ML^2 T^-1

(c) ML^2 T^-2         (d) M^2L^2 T^-2

25. Out of the following pairs, which one does not have the same dimension?

(a) force and weight      (b) pressure and stress

(c) energy and work       (d) capacitance and resistance

26. Siemens is the SI unit of

(a) electric resistance         (b) electric conductance

(c) electric capacitance      (d) electric inductance

27. The dimensions of stress are

(a) M L^-1 T^-2                 (b) ML^-1 T^-2

(c) M L^2 T^-3        (d) M L^2 T^-3 A^-2

28. The dimensions of electric resistance
are

(a) M L T-2 A
(b) M L-1 T-2 A-1
(c) M L2 T-3 A-3
(d) M L2 T-3 A-2

29. The SI unit of absorbed radiation dose of ionizing radiation is

(a) Radian          (b) Joule

(c) Watt              (d) Gray

30. The SI unit of catalytic activity is

(a) Katal           (b) Angstrom

(c) Sievert        (d) Gray

31. The SI unit of power is

(a) Henry        (b) Watt

(c) mil              (d) Sievert

32. The SI derived unit of dose equivalent is

a)  Gray        b) Katal

c) Sievert      d) Henry

33. One electron volt (ev) is a unit of energy equal to approximately

(a) 1.602 × 10-9 J         (b) 1.602 × 10-19 J

(c) 1.602 × 10-29 J       (d) 1.609 × 10-39 J

34. The dimension of gravitational  constant G are

(a) M-1 L-1 T-1       (b) M-1 L-2 T-2

(c) M-1 L-3 T-2
(d) M-1 L-2 T-3

                             

 

35. Natural units are physical units of
measurement based only on universal
physical constants. Which of the
following is a natural unit?

(a) speed of light (c)
(b) electric charge (e)
(c) characteristic impedance of free
space (z0)
(d) all of the above

36. The dimensions of Coulomb constant (k) are

(a) Q-1 M-2 L-2 T-2     (b) Q-2 M L3 T-1

(c) Q-1 ML2 T-2           (d) Q-2 ML-3 T-2

37. What are the dimensions of electricconstant (∈0)? (It is also called perimttivity of free space)

(a) Q2 M-2 L-2 T-2       (b) Q-2 M-2 L-1 T-3

(c) Q M-1 L-3 T-1          (d) Q2 M-1 L-3 T-2

38. Which of the following is SI base unit for temperature?

(a) Celsuis            (b) Kelvin

(c) Fahrenheit     (d) Rankine

39. Debye (D) is a CGS unit of

(a) electric dipole moment     (b) density

(c) temperature                         (d) mass

40. In SI units, a day consists of

(a) 56400 sec        (b) 66400 sec

 (c) 76400 sec         d) 86400 SEC

41. The unit for indicating mass on an
atomic or molecular scale is

(a) Dalton
(b) Neper
(c) Ampere
(d) Volt

 

42. The Coulomb (C) is the SI derived unit of

(a) electric current          (b) electric voltage

(c) electric charge            (d) electric field

43. The tonne (t) is a unit of mass equal to

(a) 10 kg               (b) 100 kg

(c) 1000 kg             (d) 10,000 kg

44. The SI unit for force is

(a) Volt          (b) Ampere

(c) Hertz       (d) Newton

45. The SI unit for frequency is

(a) hectre        (b) Volt

(c) Farad          (d) Hertz

46. The volt (V) is a SI derived unit of electromotive force, commonly called

(a) voltage           (b) current

(c) charge            (d) power

47. The smallest unit of mass; yoctogram (yg) equals

(a) 10-15 g         (b) 10-18 g

(c) 10-21 g           (d) 10-24 g

48. One mile equals to how many

kilometers?

(a) 0.609 km
(b) 1.609 km
(c) 2.609 km
(d) 3.609 km

 

49. Which of the following SI units is not named after any physicist?

(a) Hertz         (b) Joule

(c) Volt            (d) Candela

 

50. One yard is equivalent to

 

a) 1 foot             b)   2 feet

c)  3 feet             d) 4  feet

 

 

51. When two vectors have opposite directions, we can say that they are

(a) parallel              (b) perpendicular

(c) anti parallel       (d) none of these

52. Which of the following is a scalar quantity?

(a) weight           (b) force

(c) velocity         (d) kinetic energy (K.E.)

 

53. Which vector can be used to locate the center of mass of a collection of  particles?

(a) unit vector               (b) position vector

(c) distance vector       (d) none of the above

54. Which are the two basic properties of a vector?

(a) curvature and direction  (b) magnitude and direction

(c) magnitude and sign          (d) curvature and sign

 

 

55. Vectors are often split into two or
more orthogonal components. What is
true of these components?

(a) they are antiparallel
(b) they are the same curvature
(c) they are same magnitude
(d) they are perpendicular

56. Let i, j and k be unit vectors.   If a = 3i - j + 2k, what is the magnitude of the vector a?

(a) 4      (b) 12           (c) 14         (d)  √14

57. Which vector gives the displacement from one point to another in space?

(a) unit vector               (b) position vector

(c) distance vector       (d) none of the above

58. Which of the following is a scalar quantity?

(a) work             (b) energy

(c) power          (d) all of the above

59. A plane flying 500 MPH due north has a tail wind of 45 MPH. The resultant  velocity is

(a) 545 mph due south           (b) 455 mph due north

(c) 545 mph due north           (d) 455 mph due south

60. A man walks 3 miles north and then walks 4 miles east. The resultant  displacement is

(a) 1 mile NE               (b) 7 miles NE

(c) 5 miles NE               (d) 5 miles SE

61. A man pushes against the wall with
50 N of force. The wall does not move.
The resultant force is

(a) 50 N
(b) 100 N
(c) 75 N
(d) 0 N

 

62. The resultant magnitude of two vectors

(a) is always positive                                (b) can never be zero

(c) can be negative, positive or zero       (d) is usually zero

63. Which of the following is not true?

(a) velocity can be negative     (b) velocity is a vector

(c) speed is a scalar                    (d) speed can be negative

64. Poynting vector is closely related to

(a) power                          (b) intensity of field

(c) energy density           (d) none

65. What is the rates of 1 nanometer to 1 attometer?

(a) 106              (b) 107

(c) 108              (d) 109

66. Which of the following units is different from others?

(a) volt                     (b) kilo-watt-hour

(c) watt-sec            (d) electron-volt

 

67. The dimensional formula for torque is identical to

(a) kinetic energy                  (b) pressure energy

(c) momentum of force       (d) all of the above

68. If F = 8i - 2j and r = 6i + 8k, then F. r
will be

(a) 48 units
(b) 32 units
(c) 8 units
(d) 6 units

 

69. If P = 2i + 3j - k and Q = 4i + 6j - 2j,  then the angle between P and Q will be

(a) 0°                     (b) 45°

(c) 60°                   (d) 75°

70. Choose the only scalar?

(a) kinetic energy          (b) momentum

(c) torque                       (d) angular momentum

 

71. The magnitude of resultant of two equal forces is equal to either of the force. What is the angle between the two forces?

(a) 0°                    (b) 60°

(c) 120°               (d) 180°

72. If a body’s momentum increases by 20%, the percentage increase in its K.E. will be

(a) 30          (b) 40

(c) 44          (d) 54

73. Which of the following physical quantity has different units as compared to others?

(a) weight of a body         (b) tension in string

(c) buoyant force          (d) electromotive force (e.m.f.)

74. What is the ratio of angular speed of
minute hand and hour hand of a
watch?

(a) 1: 6
(b) 6: 1
(c) 1: 12
(d) 12: 1

75. The moment of linear momentum is called

(a) impulse           (b) torque

(c) couple             (d) angular momentum

76. When net torque acting on a system is zero, which of the following will be constant?

(a) force                                          (b) linear momentum

(c) angular momentum               (d) linear impulse

77. What is the ratio of the inertial mass to gravitational mass?

(a) 0.5                     (b) 1

(c) 2                        (d) 3

78. The dimensional formula for velocity gradient is identical to that of

(a) velocity            (b) time-period

(c) frequency        (d) angular acceleration

79. The momentum of a body decreases by 20%, the percentage decrease in  K.E. will be

(a) 28%                  (b) 36%

(c) 44%                  (d) 56%

80. Choose the physical quantity whose dimensions are different from others?

(a) kinetic energy (K.E.)         (b) pressure energy

(c) moment of force               (d) moment of momentum

81. ML0T-2 is the dimensional formula of

(a) moment of inertia
(b) viscosity
(c) surface tension
(d) angular acceleration

82. ML^2T^0 is dimensional formula for

(a) inertia                                  (b) energy

(c) moment of inertia            (d) moment of momentum

ANSWERS
1. a 2. b 3. d 4. b
5. d 6. d 7. b 8. c
9. c 10. a 11. a 12. a
13. d 14. d 15. c 16. a
17. b 18. d 19. d 20. c
21. d 22. d 23. a 24. c
25. d 26. b 27. b 28. d
29. d 30. a 31. b 32. c
33. b 34. c 35. d 36. d
37. d 38. b 39. a 40. d
41. a 42. c 43. c 44. d
45. d 46. a 47. d 48. b
49. d 50. c 51. c 52. d
53. b 54. b 55. d 56. d
57. c 58. d 59. c 60. c
61. d 62. c 63. d 64. b
65. d 66. a 67. d 68. a
69. a 70. a 71. c 72. c
73. d 74. d 75. d 76. c
77. b 78. c 79. b 80. d
81. c 82. c

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