McqMate

55

56.5k

1. |
## Gradient of a function is a constant. State True/False. |

A. | true |

B. | false |

Answer» B. false |

2. |
## The mathematical perception of the gradient is said to be |

A. | tangent |

B. | chord |

C. | slope |

D. | arc |

Answer» C. slope |

3. |
## Divergence of gradient of a vector function is equivalent to |

A. | laplacian operation |

B. | curl operation |

C. | double gradient operation |

D. | null vector |

Answer» A. laplacian operation |

4. |
## Curl of gradient of a vector is |

A. | unity |

B. | zero |

C. | null vector |

D. | depends on the constants of the vector |

Answer» C. null vector |

5. |
## Find the gradient of the function given by, x2 + y2 + z2 at (1,1,1) |

A. | i + j + k |

B. | 2i + 2j + 2k |

C. | 2xi + 2yj + 2zk |

D. | 4xi + 2yj + 4zk |

Answer» B. 2i + 2j + 2k |

6. |
## The gradient can be replaced by which of the following? |

A. | maxwell equation |

B. | volume integral |

C. | differential equation |

D. | surface integral |

Answer» C. differential equation |

7. |
## . Find the gradient of the function sin x + cos y. |

A. | cos x i – sin y j |

B. | cos x i + sin y j |

C. | sin x i – cos y j |

D. | sin x i + cos y j |

Answer» A. cos x i – sin y j |

8. |
## The divergence of a vector is a scalar. State True/False. |

A. | true |

B. | false |

Answer» A. true |

9. |
## The divergence concept can be illustrated using Pascal’s law. State True/False. |

A. | true |

B. | false |

Answer» A. true |

10. |
## Compute the divergence of the vector xi + yj + zk. |

A. | 0 |

B. | 1 |

C. | 2 |

D. | 3 |

Answer» D. 3 |

11. |
## Find the divergence of the vector yi + zj + xk. |

A. | -1 |

B. | 0 |

C. | 1 |

D. | 3 |

Answer» B. 0 |

12. |
## Find the divergence of the vector F= xe-x i + y j – xz k |

A. | (1 – x)(1 + e-x) |

B. | (x – 1)(1 + e-x) |

C. | (1 – x)(1 – e) |

D. | (x – 1)(1 – e) |

Answer» A. (1 – x)(1 + e-x) |

13. |
## Find whether the vector is solenoidal, E = yz i + xz j + xy k |

A. | yes, solenoidal |

B. | no, non-solenoidal |

C. | solenoidal with negative divergence |

D. | variable divergence |

Answer» A. yes, solenoidal |

14. |
## Find the divergence of the field, P = x2yz i + xz k |

A. | xyz + 2x |

B. | 2xyz + x |

C. | xyz + 2z |

D. | 2xyz + z |

Answer» B. 2xyz + x |

15. |
## Identify the nature of the field, if the divergence is zero and curl is also zero. |

A. | solenoidal, irrotational |

B. | divergent, rotational |

C. | solenoidal, irrotational |

D. | divergent, rotational |

Answer» C. solenoidal, irrotational |

16. |
## Curl is defined as the angular velocity at every point of the vector field. State True/False. |

A. | true |

B. | false |

Answer» A. true |

17. |
## The curl of curl of a vector is given by, |

A. | div(grad v) – (del)2v |

B. | grad(div v) – (del)2v |

C. | (del)2v – div(grad v) |

D. | (del)2v – grad(div v) |

Answer» B. grad(div v) – (del)2v |

18. |
## Which of the following theorem use the curl operation? |

A. | green’s theorem |

B. | gauss divergence theorem |

C. | stoke’s theorem |

D. | maxwell equation |

Answer» C. stoke’s theorem |

19. |
## The curl of a curl of a vector gives a |

A. | scalar |

B. | vector |

C. | zero value |

D. | non zero value |

Answer» B. vector |

20. |
## Is the vector is irrotational. E = yz i + xz j + xy k |

A. | yes |

B. | no |

Answer» A. yes |

21. |
## Find the curl of A = (y cos ax)i + (y + ex)k |

A. | 2i – ex j – cos ax k |

B. | i – ex j – cos ax k |

C. | 2i – ex j + cos ax k |

D. | i – ex j + cos ax k |

Answer» B. i – ex j – cos ax k |

22. |
## Find the curl of the vector A = yz i + 4xy j + y k |

A. | xi + j + (4y – z)k |

B. | xi + yj + (z – 4y)k |

C. | i + j + (4y – z)k |

D. | i + yj + (4y – z)k |

Answer» D. i + yj + (4y – z)k |

23. |
## Curl cannot be employed in which one of the following? |

A. | directional coupler |

B. | magic tee |

C. | isolator and terminator |

D. | waveguides |

Answer» D. waveguides |

24. |
## Which of the following Maxwell equations use curl operation? |

A. | maxwell 1st and 2nd equation |

B. | maxwell 3rd and 4th equation |

C. | all the four equations |

D. | none of the equations |

Answer» A. maxwell 1st and 2nd equation |

25. |
## The integral form of potential and field relation is given by line integral. State True/False |

A. | true |

B. | false |

Answer» A. true |

26. |
## If V = 2x2y – 5z, find its electric field at point (-4,3,6) |

A. | 47.905 |

B. | 57.905 |

C. | 67.905 |

D. | 77.905 |

Answer» B. 57.905 |

27. |
## Find the potential between a(-7,2,1) and b(4,1,2). Given E = (-6y/x2 )i + ( 6/x) j + 5 k. |

A. | -8.014 |

B. | -8.114 |

C. | -8.214 |

D. | -8.314 |

Answer» C. -8.214 |

28. |
## A field in which a test charge around any closed surface in static path is zero is called |

A. | solenoidal |

B. | rotational |

C. | irrotational |

D. | conservative |

Answer» D. conservative |

29. |
## The potential in a lamellar field is |

A. | 1 |

B. | 0 |

C. | -1 |

D. | ∞ |

Answer» B. 0 |

30. |
## Line integral is used to calculate |

A. | force |

B. | area |

C. | volume |

D. | length |

Answer» D. length |

31. |
## The energy stored in the inductor 100mH with a current of 2A is |

A. | 0.2 |

B. | 0.4 |

C. | 0.6 |

D. | 0.8 |

Answer» A. 0.2 |

32. |
## Gauss law for electric field uses surface integral. State True/False |

A. | true |

B. | false |

Answer» A. true |

33. |
## Surface integral is used to compute |

A. | surface |

B. | area |

C. | volume |

D. | density |

Answer» B. area |

34. |
## Coulomb’s law can be derived from Gauss law. State True/ False |

A. | true |

B. | false |

Answer» A. true |

35. |
## Evaluate Gauss law for D = 5r2/4 i in spherical coordinates with r = 4m and θ = π/2. |

A. | 600 |

B. | 599.8 |

C. | 588.9 |

D. | 577.8 |

Answer» C. 588.9 |

36. |
## The ultimate result of the divergence theorem evaluates which one of the following? |

A. | field intensity |

B. | field density |

C. | potential |

D. | charge and flux |

Answer» D. charge and flux |

37. |
## The divergence theorem converts |

A. | line to surface integral |

B. | surface to volume integral |

C. | volume to line integral |

D. | surface to line integral |

Answer» B. surface to volume integral |

38. |
## The triple integral is used to compute volume. State True/False |

A. | true |

B. | false |

Answer» A. true |

39. |
## The volume integral is three dimensional. State True/False |

A. | true |

B. | false |

Answer» A. true |

40. |
## Using volume integral, which quantity can be calculated? |

A. | area of cube |

B. | area of cuboid |

C. | volume of cube |

D. | distance of vector |

Answer» C. volume of cube |

41. |
## Gauss theorem uses which of the following operations? |

A. | gradient |

B. | curl |

C. | divergence |

D. | laplacian |

Answer» C. divergence |

42. |
## The Gauss divergence theorem converts |

A. | line to surface integral |

B. | line to volume integral |

C. | surface to line integral |

D. | surface to volume integral |

Answer» D. surface to volume integral |

43. |
## Find the divergence theorem value for the function given by (ez, sin x, y2) |

A. | 1 |

B. | 0 |

C. | -1 |

D. | 2 |

Answer» B. 0 |

44. |
## Divergence theorem computes to zero for a solenoidal function. State True/False. |

A. | true |

B. | false |

Answer» A. true |

45. |
## Coulomb is the unit of which quantity? |

A. | field strength |

B. | charge |

C. | permittivity |

D. | force |

Answer» B. charge |

46. |
## Coulomb law is employed in |

A. | electrostatics |

B. | magnetostatics |

C. | electromagnetics |

D. | maxwell theory |

Answer» A. electrostatics |

47. |
## Find the force between 2C and -1C separated by a distance 1m in air(in newton). |

A. | 18 x 106 |

B. | -18 x 106 |

C. | 18 x 10-6 |

D. | -18 x 10-6 |

Answer» B. -18 x 106 |

48. |
## Two charges 1C and -4C exists in air. What is the direction of force? |

A. | away from 1c |

B. | away from -4c |

C. | from 1c to -4c |

D. | from -4c to 1c |

Answer» C. from 1c to -4c |

49. |
## The Coulomb law is an implication of which law? |

A. | ampere law |

B. | gauss law |

C. | biot savart law |

D. | lenz law |

Answer» B. gauss law |

50. |
## For a charge Q1, the effect of charge Q2 on Q1 will be, |

A. | f1 = f2 |

B. | f1 = -f2 |

C. | f1 = f2 = 0 |

D. | f1 and f2 are not equal |

Answer» B. f1 = -f2 |

51. |
## The electric field intensity is defined as |

A. | force per unit charge |

B. | force on a test charge |

C. | force per unit charge on a test charge |

D. | product of force and charge |

Answer» C. force per unit charge on a test charge |

52. |
## Find the force on a charge 2C in a field 1V/m. |

A. | 0 |

B. | 1 |

C. | 2 |

D. | 3 |

Answer» C. 2 |

53. |
## Electric field intensity due to infinite sheet of charge σ is |

A. | zero |

B. | unity |

C. | σ/ε |

D. | σ/2ε |

Answer» D. σ/2ε |

54. |
## For a test charge placed at infinity, the electric field will be |

A. | unity |

B. | +∞ |

C. | zero |

D. | -∞ |

Answer» C. zero |

55. |
## The lines of force are said to be |

A. | real |

B. | imaginary |

C. | drawn to trace the direction |

D. | not significant |

Answer» C. drawn to trace the direction |

56. |
## Electric flux density in electric field is referred to as |

A. | number of flux lines |

B. | ratio of flux lines crossing a surface and the surface area |

C. | direction of flux at a point |

D. | flux lines per unit area |

Answer» B. ratio of flux lines crossing a surface and the surface area |

57. |
## The electric flux density is the |

A. | product of permittivity and electric field intensity |

B. | product of number of flux lines and permittivity |

C. | product of permeability and electric field intensity |

D. | product of number of flux lines and permeability |

Answer» A. product of permittivity and electric field intensity |

58. |
## Which of the following correctly states Gauss law? |

A. | electric flux is equal to charge |

B. | electric flux per unit volume is equal to charge |

C. | electric field is equal to charge density |

D. | electric flux per unit volume is equal to volume charge density |

Answer» D. electric flux per unit volume is equal to volume charge density |

59. |
## The Gaussian surface is |

A. | real boundary |

B. | imaginary surface |

C. | tangential |

D. | normal |

Answer» B. imaginary surface |

60. |
## A point charge 2nC is located at origin. What is the potential at (1,0,0)? |

A. | 12 |

B. | 14 |

C. | 16 |

D. | 18 |

Answer» D. 18 |

61. |
## Find the potential of V = 60sin θ/r2 at P(3,60,25) |

A. | 5.774 |

B. | 6.774 |

C. | 7.774 |

D. | 8.774 |

Answer» A. 5.774 |

62. |
## The potential difference in an open circuit is |

A. | zero |

B. | unity |

C. | infinity |

D. | circuit does not exist open |

Answer» C. infinity |

63. |
## The potential taken between two points across a resistor will be |

A. | positive |

B. | negative |

C. | zero |

D. | infinity |

Answer» B. negative |

64. |
## What is the potential difference between 10sinθcosφ/r2 at A(1,30,20) and B(4,90,60)? |

A. | 2.386 |

B. | 3.386 |

C. | 4.386 |

D. | 5.386 |

Answer» C. 4.386 |

65. |
## The voltage at any point in an ac circuit will be |

A. | peak voltage |

B. | rms voltage |

C. | average voltage |

D. | source voltage |

Answer» B. rms voltage |

66. |
## Divergence theorem is based on |

A. | gauss law |

B. | stoke’s law |

C. | ampere law |

D. | lenz law |

Answer» A. gauss law |

67. |
## The Gaussian surface for a line charge will be |

A. | sphere |

B. | cylinder |

C. | cube |

D. | cuboid |

Answer» B. cylinder |

68. |
## The Gaussian surface for a point charge will be |

A. | cube |

B. | cylinder |

C. | sphere |

D. | cuboid |

Answer» C. sphere |

69. |
## The total charge of a surface with densities 1,2,…,10 is |

A. | 11 |

B. | 33 |

C. | 55 |

D. | 77 |

Answer» C. 55 |

70. |
## The work done by a charge of 10μC with a potential 4.386 is (in μJ) |

A. | 32.86 |

B. | 43.86 |

C. | 54.68 |

D. | 65.68 |

Answer» B. 43.86 |

71. |
## Gauss law cannot be used to find which of the following quantity? |

A. | electric field intensity |

B. | electric flux density |

C. | charge |

D. | permittivity |

Answer» D. permittivity |

72. |
## Gauss law for magnetic fields is given by |

A. | div(e) = 0 |

B. | div(b) = 0 |

C. | div(h) = 0 |

D. | div(d) = 0 |

Answer» B. div(b) = 0 |

73. |
## Gauss law can be used to compute which of the following? |

A. | permittivity |

B. | permeability |

C. | radius of gaussian surface |

D. | electric potential |

Answer» C. radius of gaussian surface |

74. |
## Gauss law can be evaluated in which coordinate system? |

A. | cartesian |

B. | cylinder |

C. | spherical |

D. | depends on the gaussian surface |

Answer» D. depends on the gaussian surface |

75. |
## Gauss law cannot be expressed in which of the following forms? |

A. | differential |

B. | integral |

C. | point |

D. | stokes theorem |

Answer» D. stokes theorem |

76. |
## With Gauss law as reference which of the following law can be derived? |

A. | ampere law |

B. | faraday’s law |

C. | coulomb’s law |

D. | ohm’s law |

Answer» C. coulomb’s law |

77. |
## The electric flux density and electric field intensity have which of the following relation? |

A. | linear |

B. | nonlinear |

C. | inversely linear |

D. | inversely nonlinear |

Answer» A. linear |

78. |
## Find the potential at a point (4, 3, -6) for the function V = 2x2y + 5z. |

A. | 96 |

B. | 66 |

C. | 30 |

D. | -66 |

Answer» B. 66 |

79. |
## Find the potential of the function V = 60cos θ/r at the point P(3, 60, 25). |

A. | 20 |

B. | 10 |

C. | 30 |

D. | 60 |

Answer» B. 10 |

80. |
## Find the work done moving a charge 2C having potential V = 24volts is |

A. | 96 |

B. | 24 |

C. | 36 |

D. | 48 |

Answer» D. 48 |

81. |
## The distance vector is obtained in |

A. | cartesian coordinate system |

B. | spherical coordinate system |

C. | circular coordinate system |

D. | space coordinate system |

Answer» D. space coordinate system |

82. |
## The divergence of distance vector is |

A. | 0 |

B. | 3 |

C. | 2 |

D. | 1 |

Answer» B. 3 |

83. |
## Find a vector normal to a plane consisting of points p1(0,1,0), p2(1,0,1) and p3(0,0,1) |

A. | –j – k |

B. | –i – j |

C. | –i – k |

D. | –i – j – k |

Answer» A. –j – k |

84. |
## The unit vector to the points p1(0,1,0), p2(1,0,1), p3(0,0,1) is |

A. | (-j – k)/1.414 |

B. | (-i – k)/1.414 |

C. | (-i – j)/1.414 |

D. | (-i – j – k)/1.414 |

Answer» A. (-j – k)/1.414 |

85. |
## The polar form of Cartesian coordinates is |

A. | circular coordinates |

B. | spherical coordinates |

C. | cartesian coordinates |

D. | space coordinates |

Answer» A. circular coordinates |

86. |
## The work-electric field relation is given by |

A. | volume integral |

B. | surface integral |

C. | line integral |

D. | relation impossible |

Answer» C. line integral |

87. |
## The distance vector can be used to compute which of the following? |

A. | dot product |

B. | cross product |

C. | unit normal vector |

D. | area |

Answer» C. unit normal vector |

88. |
## Distance and position vectors rely on field strength. State True/False. |

A. | true |

B. | false |

Answer» A. true |

89. |
## Find the projection of A on B. Given A = 10j + 3k and B = 4j + 5k. |

A. | 6 |

B. | 6.25 |

C. | 6.5 |

D. | 6.75 |

Answer» B. 6.25 |

90. |
## The del operator is called as |

A. | gradient |

B. | curl |

C. | divergence |

D. | vector differential operator |

Answer» D. vector differential operator |

91. |
## The relation between vector potential and field strength is given by |

A. | gradient |

B. | divergence |

C. | curl |

D. | del operator |

Answer» A. gradient |

92. |
## The Laplacian operator is actually |

A. | grad(div v) |

B. | div(grad v) |

C. | curl(div v) |

D. | div(curl v) |

Answer» B. div(grad v) |

93. |
## The divergence of curl of a vector is zero. State True or False. |

A. | true |

B. | false |

Answer» A. true |

94. |
## The curl of gradient of a vector is non-zero. State True or False. |

A. | true |

B. | false |

Answer» B. false |

95. |
## Identify the correct vector identity. |

A. | i . i = j . j = k . k = 0 |

B. | i x j = j x k = k x i = 1 |

C. | div (u x v) = v . curl(u) – u . curl(v) |

D. | i . j = j . k = k . i = 1 |

Answer» C. div (u x v) = v . curl(u) – u . curl(v) |

96. |
## A vector is said to be solenoidal when its |

A. | divergence is zero |

B. | divergence is unity |

C. | curl is zero |

D. | curl is unity |

Answer» A. divergence is zero |

97. |
## The magnetic field intensity is said to be |

A. | divergent |

B. | curl free |

C. | solenoidal |

D. | rotational |

Answer» C. solenoidal |

98. |
## A field has zero divergence and it has curls. The field is said to be |

A. | divergent, rotational |

B. | solenoidal, rotational |

C. | solenoidal, irrotational |

D. | divergent, irrotational |

Answer» B. solenoidal, rotational |

99. |
## When a vector is irrotational, which condition holds good? |

A. | stoke’s theorem gives non-zero value |

B. | stoke’s theorem gives zero value |

C. | divergence theorem is invalid |

D. | divergence theorem is valid |

Answer» B. stoke’s theorem gives zero value |

100. |
## The Cartesian system is also called as |

A. | circular coordinate system |

B. | rectangular coordinate system |

C. | spherical coordinate system |

D. | space coordinate system |

Answer» B. rectangular coordinate system |

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