Engineering Physics MCQs TT-1 (March 2021)

Post by : Sachin Dabhade ( Data Science )

When it comes to physic, I think most of us have considered that physics is not a scoring subject and might be thinking right but because it's not a scoring subject we can't ignore him. We are engineers, and in the future physics is continued to tense us, so why wait for the future. If we clear our basic concept of physics and just regularly solve the problems by increasing the hardness. Then we can actually grab the physics solutions as well. I think fear is the worst thing in our life which affects our entire behavior and scalability. So, be confident about your concept and try to solve at least five examples a day. And see the results, you will rock.

Engineering Physics MCQs

RCPIT Examination, Shirpur.

Type 1: Multiple Choice Questions - 1 Marks

1) X-ray is

a) Electromagnetic wave

b) Sound wave

c) Ultrasonic wave

d) Matter wave

Ans: a

2) The condition for Braggs law of diffraction is

a) 2d sinθ = nλ

b) 2d cosθ = nλ

c) 2d sinθ = nλ/2

d) 2d cosθ = nλ/2

Ans: a

3) The position of Fermi level in p-type semiconductor lies

a) Near conduction band

b) Exactly middle of valence & conduction band

c) Near valence band

d) in the valence band

Ans: c

4) The Zener diode working on the principle of

a) Avalanche break down

b) Photovoltaic effect

c) Tunneling effect

d) All of above

Ans: c

5) If the plane is parallel to certain axis then the corresponding Miller Indices is

a) 1

b) 2

c) ∞

d) 0

Ans: d

6) The Miller Indices of the plane are (210), the corresponding intercepts are

a) 1/2, 1, 0

b) 1/2, 1, ∞

c) 1, 2, 0

d) 2, 1, ∞

Ans: b

7) The position of Fermi level in intrinsic semiconductor at high temperature is

a) Near conduction band

b) Exactly middle of valence & conduction band

c) Near valence band

d) in conduction band

Ans: b

8) In LED the wavelength of emitted light is depend on

a) Current across LED

b) Potential barrier

c) bias voltage

d) Energy band gap (Eg)

Ans: d

9) The position of Fermi level in intrinsic semiconductor at high doping concentration is

a) Near valence band

b) Exactly middle of valence & conduction band

c) Near conduction band

d) Question is invalid

Ans: d

10) For n- type semiconductor Hall coefficient is

a) Negative

b) Positive

c) Neutral

d) None of these

Ans: a

11) Repeatable entity of a crystal structure is known as

(a) Crystal

(b) Lattice

(d) Miller indices

Ans: c

12) The wavelength of X-ray is in the range of

a) 0.1 to 100 A°

b) 0.1 to 100 μm

c) 0.1 to 100 mm

d) None of above

Ans: a

13) Lowest unfilled energy band is called

a) Valence band

b) Forbidden band

c) Conduction band

d) Inner filled band

Ans: c

14) The majority charge carriers in n-type semiconductor is

a) Both electrons & holes

b) holes

c) electrons

d) none of these

Ans: c

15) If trivalent impurity are added in pure semiconductor the resultant semiconductor is

a) Intrinsic

b) n-type

c) p -type

d) None of above

Ans: c

16) The position of Fermi level in intrinsic semiconductor lies

a) Near conduction band

b) Exactly middle of valence & conduction band

c) Near valence band

d) in valence band

Ans: b

17) Hall effect is used for which of the following

a) Determining carrier concentrations

b) calculate mobility

c) Determining type of semiconductor

d) All of these

Ans: d

18) For p- type semiconductor Hall coefficient is

a) Negative

b) Positive

c) Neutral

d) None of these

Ans: b

19) Zener breakdown is occur when connected in

a) Forward bias

b) reverse bias

c) In series

d) None of above

Ans: b

20) LED can convert electrical energy into -------------

a) Heat

b) Thermal

c) Light

d) None of above

Ans: c

21) The correct expression for Bragg’s law is nλ = ___________

a) dsinθ,

b) dcosθ,

c) 2dsinθ,

d) 2dcosθ

Ans: c

22) X-ray have

a) shorter wavelength,

b) high frequency,

c) both A and B,

d) longest wavelength

Ans: c

23) Hall potential is inversely proportional to magnetic flux density.

a) True,

b) False

Ans: b

24) When the temperature of either n-type or p-type increases, determine the movement of the position of the Fermi energy level?

a) Towards center of energy gap,

b) Towards down of energy gap

c) Towards up of energy gap,

d) Towards out of page

Ans: a

25) Which of the following is known as indirect band gap semiconductors?

a) Germanium,

b) Nickel,

c) GaAs

d) Silicon

Ans: c

26) When forward biased, LED emits light because of

a) Light produced by collisions

b) Light generated in breaking the covalent bonds

c) Recombination of carriers

d) All of the above reasons

Ans: c

27) Solar cell convert

a) Electrical energy into mechanical energy,

b) Solar energy into biological energy

c) Solar energy into Electrical energy,

d) Electrical energy into Solar energy

Ans: c

28) Depletion region of Zener diode is,

a) Thick

b) Thin

c)very thick

d) very thin

Ans: d

29) In simple cubic crystal, the Miller indices of the plane (1 2 -1). the given plane intercepts the axes at-----

a) m= a, n = b/2, p = - c ,

b) m= 2a, n = 2b, p = - c

c) m= a, n = -b, p = 2c,

d) m= 2a, n = b, p = -2c

Ans: a

30) The cathode in the Coolidge tube is made of which of the following elements?

a) Quartz,

b) Iron,

c) Tungsten,

d) Barium

Ans: c

31) X-rays can be deflected by

a) Electric Field

b) Magnetic Field

c) Both

d) None

Ans: d

32) Miller Indices of the plane parallel to Y and Z axes are

a) (100)

b) (010)

c) (001)

d) (101)

Ans: a

33) X-rays are emitted when

a) High energy electrons hit the substance of low molecular weight

b) High energy electrons hit a substance of high molecular weight

c) Low energy electrons hit any substance

d) Low energy electrons hit a substance of high molecular weight

Ans: b

34) In X-rays it is observed that for certain values of glancing angle ,the current

a) Decreases

b) Increases

c) Remains stable

d) Equals to glancing angle

Ans: b

35) In Bragg’s law 2dsinθ=nλ,d is called as

a) diameter

b) Interplaner spacing

c) Angle between incident ray and normal

d) Order of the spectrum

Ans: b

36) X-ray is

a) Electromagnetic wave

b) Sound wave

c) Ultrasonic wave

d) Matter wave

Ans: a

37) The Miller indices for set of parallel planes are

a) Different

b) zero

c) same

d) none of above

Ans: c

38) Charge carriers inside the semiconductor is

a) Both electrons &holes

b) Only holes

c) Only electrons

d) None of these

Ans: a

39) The position of Fermi level in semiconductor is found by

a) Fermi-Dirac equation

b) Bose-Einstein equation

c) Maxwell-Boltzmann equation

d) All of above

Ans: a

40) Hall effect is used for which of the following

a) Determining carrier concentrations

b) calculate mobility

c) Determining type of semiconductor

d) All of these

Ans: d

41) Fermi level for extrinsic semiconductor depends on

a) Donor element

b) Impurity concentration

c) Temperature

d) All above

Ans: c

42) The center of gravity of the conduction electrons and holes is known as

a) Fermi level

b) Donor level

c) Acceptor level

d) All above

Ans: a

43) Fermi energy level for p-type extrinsic semiconductors at zero temp lies

a) At middle of the band gap

b) Close to conduction band

c) Close to valence band

d) None of above

Ans: c

44) The Solar cell working on the principle of

a) Photoelectric effect

b) Compton effect

c) Photovoltaic effect

d) Tunneling effect

Ans: c

45) The Zener diode working on the principle of

a) Photoelectric effect

b) Compton effect

c) Photovoltaic effect

d) Tunneling effect

Ans: d

46) The Zener diode used for

a) Voltage regulation

b) Current regulation

c) Frequency regulation

d) All above

Ans: d

47) The position of Fermi level in intrinsic semiconductor at low doping concentration is

a) Near valence band

b) Exactly middle of valence & conduction band

c) Near conduction band

d) Question is invalid

Ans: d

48) The position of Fermi level in p-type semiconductor at extremely high doping concentration is

a) Near valence band

b) Exactly middle of valence & conduction band

c) Lie inside the valence band

d) Near conduction band

Ans: c

49) The position of Fermi level in n-type semiconductor at extremely high doping concentration is

a) Near valence band

b) Exactly middle of valence & conduction band

c) Lie inside the conduction band

d) Near conduction band

Ans: c

50) The Fermi level is a uppermost filled energy level at ----------- temperature.

a) Absolute zero

b) 0o C

c) very high

d) All above

Ans: a

51) In simple cubic crystal, the given plane has intercepts along the axes at (∞, ∞, c/2) the corresponding Miller indices of the plane are -----

a) (020)

b) (002)

c)(102)

d) (202)

Ans: b

52) In simple cubic crystal, the given plane has intercepts along the axes at (-a, b/3, ∞) the corresponding Miller indices of the plane are -----

a) (130)

b) (130)

c)(310)

d) (103)

Ans: a

53) In simple cubic crystal, the given plane has intercepts along the axes at (-a/2, b,-c/2) the corresponding Miller indices of the plane are -----

a) (212)

b) (202)

c)(212)

d) (212)

Ans: d

54) In simple cubic crystal, the given plane has intercepts along the axes at (a, -b,-c/3) the corresponding Miller indices of the plane are -----

a) (113)

b) (103)

c)(311)

d) (113)

Ans: a

55) In interplaner spacing formula, interplaner spacing (dhkl) is directly proportional to

a) Lattice constant (a)

b) Miller indices (hkl)

c) wavelength (λ)

d) All above

Ans: a

56) In interplaner spacing (dhkl) is nothing but the distance between two ---------- planes

a) Perpendicular

b) Parallel

c) Intersecting

d) None of above

Ans: b

57) In bragg’s spectrometer the ionization chamber is filled with ---------- gas.

a) Methyl

b) Methyl Bromide

c) Bromide

d) None of above

Ans: b

58) In direct band gap semiconductor maximum of valence band and minimum of conduction band lie at same values of ----------.

a) Propagation vector (k)

b) Momentum (p)

c) Both a) & b)

d) None of above

Ans: c

59) In indirect band gap semiconductor maximum of valence band and minimum of conduction band lie at different values of ----------.

a) Propagation vector (k)

b) Momentum (p)

c) Both a) & b)

d) None of above

Ans: c

60) In direct band gap semiconductor maximum of valence band and minimum of conduction band lie at -------- values of propagation vector (k).

a) Same

b) Different

c) Both a) & b)

d) None of above

Ans: a

61) In indirect band gap semiconductor maximum of valence band and minimum of conduction band lie at -------- values of propagation vector (k).

a) Same

b) Different

c) Both a) & b)

d) None of above

Ans: b

62) In direct band gap semiconductor maximum of valence band and minimum of conduction band lie at -------- values of momentum (p).

a) Same

b) Different

c) Both a) & b)

d) None of above

Ans: a

63) In indirect band gap semiconductor maximum of valence band and minimum of conduction band lie at -------- values of momentum (p).

a) Same

b) Different

c) Both a) & b)

d) None of above

Ans: b

64) If the angle of incidence is 30°, then the wavelength for first-order spectrum is equal to __________

a) d

b) 2d

c) d/2

d) d/3

Ans: a

65) X-rays possess electromagnetic character.

a) True

b) False

Ans: a

66) In a N-type semiconductor, the position of Fermi-level

a) Is lower than the center of energy gap

b) Is at the center of energy gap

c) Is higher than the center of energy gap

d) Can be any where

Ans: c

67) Holes are the majority carries in Intrinsic Semiconductors.

a) True

b) False

Ans: b

68) In a P-N Junction, the depletion region is reduced when _________

a) P side is connected to the negative terminal of a battery

b) P side is connected to the positive terminal of a battery

c) N side is connected to the positive terminal of a battery

d) Never reduced

Ans: b

69) Hall effect can be used to measure

a) Magnetic field intensity

b) Electric field intensity

c) Carrier concentration

d) None of the above

Ans: c

70) In Hall effect, the output voltage produced across the crystal is due to

a) Drop across the crystal is due to the current passed through it

b) Induced voltage by the applied magnetic field

c) Movement of charge carriers towards one end

d) All of the above

Ans: c

71) The energy gap in a semiconductor

a) Increases with temperature

b) Does not change with temperature

c) Is zero

d) Decreases with temperature

Ans: d

72) The process of adding impurities to a pure semiconductor is called

a) Mixing

b) Doping

c) Diffusing

d) None of the above

Ans: b

73) What should be the biasing of the LED?

a) Forward bias than Reverse bias

b) Reverse bias

c) Forward bias

d) No biasing required

Ans: c

74) Which of the following would have highest wavelength?

(a) A

(b) B

(d) D

Ans: a

75) What is the level of doping in Zener Diode?

a) Lightly Doped

b) Heavily Doped

c) Moderately Doped

d) No doping

Ans: b

76) The following graph depicts the I-V characteristics of which instrument?

a) Photodiode

b) Light Emitting Diode

c) Solar Cell

d) Zener diode

Ans: c

77) The mobility of electrons in a material is expressed in unit of:

a) V/s

b) m2 /V-s

c) m2 /s

d) J/K

Ans: b

78) How many junction do a diode consist?

a) 0

b) 1

c) 2

d) 3

Ans: b

79) Symbol for the Zener diode

a) Symbol

b) Symbol

c) Symbol

d) Symbol

Ans: a

80) In free space, X-ray travels in ______________

a) Periodic oscillations

b) Non-Periodic oscillations

c) Zig-zag path

d) Straight line

Ans: d

81) How does a semiconductor behave at absolute zero?

a) Conductor

b) Insulator

c) Semiconductor

d) Protection device

Ans: b

82) What are the charge carriers in semiconductors?

a) Electrons and holes

b) Electrons

c) Holes

d) Charges

Ans: a

83) EF = (Ec+ Ev)/2, this represents the Fermi energy level of which of the following?

a) Extrinsic semiconductor

b) N-type semiconductor

c) P-type semiconductor

d) Intrinsic semiconductor

Ans: d

84) -------is used as a target in Coolidge tube for product. X- ray tube

a) Copper

b) Silver

c) Helium

d) Molybdenum

Ans: d

85) The crystal lattice has a _________ arrangement.

a) One-dimensional

b) Two-dimensional

c) Three-dimensional

d) Four-dimensional

Ans: c

86) A reverse bias pn junction has …………

a) Very narrow depletion layer

b) Almost no current

c) Very low resistance

d) Large current flow

Ans: b

87) pn junction acts as a ……….

a) Controlled switch

b) Bidirectional switch

c) Unidirectional switch

d) None of the above

Ans: c

88) In p-type semiconductors, number of holes __________ number of electrons.

a) Equal

(b) Greater than

(d) Twice

Ans: b

89) In a Zener diode

(a) Negative resistance characteristic exists

(b) Forward voltage rating is high

(d) All of the above

Ans: c

90) LED emits

(a) Microwave radiation

(b) Visible and IR radiation

(d) X-rays

Ans: b

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