Class 12 Physics Ch-11 Dual Nature of Radiation and Matter MCQs Exam 2027

Chapter: Dual Nature of Radiation and Matter

Part 1: Electron, Cathode Rays & Specific Charge

1. Cathode rays are a group of: [BSEB, 2026]

   (A) Electrons

   (B) Protons

   (C) Neutrons

   (D) Atoms

2. Cathode rays are: [BSEB, 2024 (A)]

   (A) Negatively charged particles

   (B) Positively charged particles

   (C) Neutral particles

   (D) Photons

3. The specific charge of an electron ($e/m$) is: [BSEB, 2025]

   (A) $1.8 \times 10^{11} \text{ C/kg}$

   (B) $1.8 \times 10^{-19} \text{ C/kg}$

   (C) $1.9 \times 10^{-11} \text{ C/kg}$

   (D) $1.7 \times 10^{10} \text{ C/kg}$

4. Which of the following is correct for the charge on an electron? [BSEB, 2022]

   (A) $1.6 \times 10^{-16} \text{ C}$

   (B) $1.6 \times 10^{-17} \text{ C}$

   (C) $1.6 \times 10^{-18} \text{ C}$

   (D) $1.6 \times 10^{-19} \text{ C}$

5. Cathode rays are deflected in: [BSEB, 2019]

   (A) Magnetic field only

   (B) Electric field only

   (C) Both magnetic and electric fields

   (D) None of these

6. Millikan’s oil drop method is used to determine: [BSEB]

   (A) Mass of electron

   (B) Charge of electron

   (C) Velocity of electron

   (D) None of these

7. The mass of an electron ($m$) is: [BSEB]

   (A) $9.1 \times 10^{-31} \text{ kg}$

   (B) $1.6 \times 10^{-27} \text{ kg}$

   (C) $9.1 \times 10^{-25} \text{ kg}$

   (D) Zero

8. What is measured by Thomson’s method for an electron? [BSEB]

   (A) Momentum

   (B) Mass only

   (C) Specific charge ($e/m$)

   (D) Charge only

9. The charge on an $\alpha$-particle is: [BSEB]

   (A) $e$

   (B) $2e$

   (C) $4e$

   (D) Zero

10. Who proved electron as the ‘fundamental particle of matter’? [BSEB]

    (A) Rutherford

    (B) J. J. Thomson

    (C) Millikan

    (D) Bohr

11. The velocity of cathode rays is: [BSEB]

    (A) Equal to velocity of light

    (B) Nearly 1/10th of the velocity of light

    (C) Equal to velocity of sound

    (D) Infinite

12. Electron volt ($eV$) is the unit of: [BSEB, 2020]

    (A) Charge

    (B) Potential difference

    (C) Energy

    (D) Power

13. The value of $1 \text{ eV}$ is: [BSEB, 2024]

    (A) $1.6 \times 10^{-19} \text{ J}$

    (B) $1.6 \times 10^{-18} \text{ J}$

    (C) $3.2 \times 10^{-19} \text{ J}$

    (D) $1 \text{ J}$

14. What is emitted in thermionic emission? [BSEB]

    (A) Photons

    (B) Electrons

    (C) Protons

    (D) Neutrons

15. The properties of cathode rays are similar to: [BSEB]

    (A) $\alpha$-rays

    (B) $\beta$-rays

    (C) $\gamma$-rays

    (D) X-rays

16. Which layer is coated on the cathode in a photoelectric cell? [BSEB]

    (A) Copper

    (B) Photosensitive material

    (C) Iron

    (D) Insulator

17. The unit of specific charge is: [BSEB]

    (A) $\text{C-kg}$

    (B) $\text{C/kg}$

    (C) $\text{kg/C}$

    (D) $\text{Coulomb}$

18. Cathode rays are: [BSEB]

    (A) Stream of fast moving electrons

    (B) Electromagnetic waves

    (C) Stream of positively charged particles

    (D) None of these

19. The credit for the discovery of electron goes to: [BSEB]

    (A) Goldstein

    (B) Thomson

    (C) Chadwick

    (D) Rutherford

20. Kinetic energy of an electron accelerated through $V$ volt is: [BSEB]

    (A) $eV$

    (B) $V/e$

    (C) $e/V$

    (D) $e^2 V$

21. The rate of thermionic emission depends on: [BSEB]

    (A) Nature of material only

    (B) Temperature only

    (C) Both nature of material and temperature

    (D) Intensity of light

22. Photoelectric effect is a: [BSEB]

    (A) Chemical phenomenon

    (B) Physical phenomenon

    (C) Atomic phenomenon

    (D) None of these

23. The mass of cathode rays is: [BSEB]

    (A) Same as proton

    (B) Same as mass of electron

    (C) Zero

    (D) Infinite

24. Cathode rays produce what on a fluorescent screen? [BSEB]

    (A) Fluorescence

    (B) Heat

    (C) Sound

    (D) Magnetism

25. In which year was the electron discovered? [BSEB]

    (A) 1905

    (B) 1897

    (C) 1920

    (D) 1850

26. For electric discharge in gases, what is required? [BSEB]

    (A) High pressure

    (B) Low pressure

    (C) Low potential difference

    (D) None of these

27. The glowing of glass opposite to cathode in a discharge tube is called: [BSEB]

    (A) Reflection

    (B) Fluorescence

    (C) Refraction

    (D) Diffraction

28. The penetrating power of cathode rays is: [BSEB]

    (A) Very low

    (B) Very high

    (C) Zero

    (D) Moderate

29. What force acts on an oil drop in Millikan’s experiment? [BSEB]

    (A) Gravitational force only

    (B) Electric force only

    (C) Both gravitational and electric forces

    (D) Magnetic force

30. The mass of an electron is approximately what part of the mass of a proton? [BSEB]

    (A) 1/100

    (B) 1/1840

    (C) 1/1000

    (D) 2 times

Part 2: Photon & Quantum Theory

31. The energy ($E$) of a photon is: [BSEB, 2022]

    (A) $h\nu$

    (B) $h/\nu$

    (C) $\nu/h$

    (D) $h\nu/c$

32. The rest mass of a photon is: [BSEB, 2021]

    (A) Zero

    (B) Infinite

    (C) $9.1 \times 10^{-31} \text{ kg}$

    (D) $1.6 \times 10^{-27} \text{ kg}$

33. The momentum ($p$) of a photon is: [BSEB, 2026]

    (A) $\lambda/h$

    (B) $h/\lambda$

    (C) $hc/\lambda$

    (D) $h$

34. The SI unit of Planck’s constant ($h$) is: [BSEB]

    (A) $Js^{-1}$

    (B) $J^{-1}s$

    (C) $Js$

    (D) $J$

35. The value of Planck’s constant is: [BSEB]

    (A) $6.626 \times 10^{-34} \text{ Js}$

    (B) $6.6 \times 10^{-27} \text{ erg-s}$

    (C) Both (A) and (B)

    (D) None

36. Energy of a photon with wavelength $\lambda$ is: [BSEB, 2019]

    (A) $hc\lambda$

    (B) $hc/\lambda$

    (C) $h\lambda/c$

    (D) $\lambda/hc$

37. The formula for the kinetic mass of a photon is: [BSEB, 2025]

    (A) $h\nu/c$

    (B) $h\nu/c^2$

    (C) $hc/\nu$

    (D) $c^2/h\nu$

38. The particle nature of light is confirmed by: [BSEB, 2023]

    (A) Interference

    (B) Diffraction

    (C) Photoelectric effect

    (D) Polarization

39. Which of the following is charge-less? [BSEB, 2021]

    (A) $\alpha$-particle

    (B) $\beta$-particle

    (C) Photon

    (D) Proton

40. The dimensions of Planck’s constant are same as: [BSEB]

    (A) Force

    (B) Work

    (C) Angular momentum

    (D) Power

41. A quantum of radiation is called: [BSEB, 2018]

    (A) Proton

    (B) Photon

    (C) Deuteron

    (D) Electron

42. Relation between energy ($E$) and momentum ($p$) of a photon is: [BSEB, 2026]

    (A) $E = pc^2$

    (B) $E = pc$

    (C) $E = p/c$

    (D) $E = \sqrt{pc}$

43. The momentum of a photon of energy $h\nu$ is: [BSEB]

    (A) $h\nu/c$

    (B) $h\nu/c^2$

    (C) $h/c$

    (D) $h\lambda$

44. The energy range of a visible light photon is approximately: [BSEB]

    (A) $0.5 – 1.0 \text{ eV}$

    (B) $1.6 – 3.2 \text{ eV}$

    (C) $10 – 20 \text{ eV}$

    (D) $100 – 500 \text{ eV}$

45. The path of a photon is: [BSEB]

    (A) Circular

    (B) Straight line

    (C) Parabolic

    (D) Random

46. On increasing the wavelength $\lambda$ of a photon, its energy: [BSEB]

    (A) Increases

    (B) Decreases

    (C) Remains unchanged

    (D) Becomes zero

47. Which statement is true for a photon? [BSEB]

    (A) Its velocity does not depend on medium

    (B) It deflects in magnetic field

    (C) Its velocity is equal to the velocity of light

    (D) It is a physical particle

48. According to Einstein, light travels in small packets of energy called: [BSEB]

    (A) Electrons

    (B) Protons

    (C) Photons or Quanta

    (D) Neutrons

49. Number of photons in $6.62 \text{ J}$ of radiated energy of frequency $10^{14} \text{ Hz}$ will be: [BSEB, 2018]

    (A) $10^{10}$

    (B) $10^{15}$

    (C) $10^{20}$

    (D) $10^{25}$

50. Dual nature of light means light behaves as: [BSEB]

    (A) Particle only

    (B) Wave only

    (C) Both particle and wave

    (D) Neither of these

51. Photon energy is maximum for: [BSEB]

    (A) $\gamma$-rays

    (B) X-rays

    (C) Infrared rays

    (D) Visible light

52. The dimension of Planck’s constant ($h$) is: [BSEB]

    (A) $[ML^2T^{-1}]$

    (B) $[ML^2T^{-2}]$

    (C) $[MLT^{-1}]$

    (D) $[ML^2T]$

53. A photon exists: [BSEB]

    (A) Only in rest state

    (B) Only in motion state

    (C) In both

    (D) In neither

54. The energy of a quantum of electromagnetic radiation is: [BSEB]

    (A) $h\nu$

    (B) $h/\nu$

    (C) $\nu/h$

    (D) $h\lambda$

55. If the frequency of a photon is doubled, its momentum: [BSEB]

    (A) Becomes half

    (B) Becomes double

    (C) Becomes four times

    (D) Remains unchanged

56. Energy of infrared photon is _______ than visible light: [BSEB]

    (A) More

    (B) Less

    (C) Equal

    (D) Very much more

57. When is the kinetic mass of a photon zero? [BSEB]

    (A) When velocity is $c$

    (B) When velocity $v < c$

    (C) Never (Rest mass is zero)

    (D) Always

58. According to Planck’s quantum theory, energy is emitted: [BSEB]

    (A) Continuously

    (B) In discrete packets

    (C) As waves

    (D) None of these

59. The speed of a photon in vacuum is: [BSEB]

    (A) $3 \times 10^8 \text{ m/s}$

    (B) $3 \times 10^{10} \text{ m/s}$

    (C) $332 \text{ m/s}$

    (D) Zero

60. If energy of a photon is $E$, then its wavelength $\lambda$ will be: [BSEB, 2020]

    (A) $hc/E$

    (B) $E/hc$

    (C) $hE/c$

    (D) $c/hE$

Part 3: Photoelectric Effect: Work Function & Threshold Frequency

61. The minimum frequency required to start photoelectric emission from a surface is called: [BSEB, 2015]

    (A) Wave frequency

    (B) Threshold frequency

    (C) Photon frequency

    (D) Maximum frequency

62. The work function ($\phi_0$) of Sodium (Na) is: [BSEB, 2022]

    (A) $2.35 \text{ eV}$

    (B) $2.65 \text{ eV}$

    (C) $2.75 \text{ eV}$

    (D) $2.14 \text{ eV}$

63. Work function is generally measured in: [BSEB, 2016]

    (A) Joule

    (B) Watt

    (C) Electron-volt ($eV$)

    (D) Ampere

64. The value of photoelectric current at threshold frequency ($\nu_0$) is: [BSEB, 2014]

    (A) Maximum

    (B) Minimum

    (C) Zero

    (D) None of these

65. Which of the following metals has minimum work function? [BSEB]

    (A) Iron

    (B) Copper

    (C) Barium

    (D) Cesium (Cs)

66. The value of work function for Platinum is approximately: [BSEB]

    (A) $5.65 \text{ eV}$

    (B) $2.27 \text{ eV}$

    (C) $4.00 \text{ eV}$

    (D) $1.00 \text{ eV}$

67. Relation between threshold wavelength ($\lambda_0$) and work function ($W$) is: [BSEB]

    (A) $W = hc/\lambda_0$

    (B) $W = h\lambda_0/c$

    (C) $W = \lambda_0/hc$

    (D) $W = h\nu$

68. Threshold wavelength of Sodium is $6800 \text{ \AA}$. Its work function will be: [BSEB]

    (A) $1.8 \text{ eV}$

    (B) $2.5 \text{ eV}$

    (C) $4.0 \text{ eV}$

    (D) $1.0 \text{ eV}$

69. Threshold wavelength for a metal is $5000 \text{ \AA}$. Emission is possible if incident light is: [BSEB]

    (A) $4500 \text{ \AA}$

    (B) $5500 \text{ \AA}$

    (C) $6000 \text{ \AA}$

    (D) $7000 \text{ \AA}$

70. If work function is $2.8 \text{ eV}$, then threshold wavelength will be: [BSEB, 2024]

    (A) $4000 \text{ \AA}$

    (B) $4433 \text{ \AA}$

    (C) $5000 \text{ \AA}$

    (D) $3000 \text{ \AA}$

71. Effective radiation for electron emission from Zinc surface is: [BSEB]

    (A) Visible light

    (B) Infrared rays

    (C) Ultraviolet rays

    (D) Microwaves

72. Work function of a metal is the minimum energy required to: [BSEB]

    (A) Ionize the atom

    (B) Extract electron from the surface

    (C) Accelerate the electron

    (D) None of these

73. On a metal with $5 \text{ eV}$ work function, a $4 \text{ eV}$ photon falls: [BSEB]

    (A) Electrons will emit

    (B) Electrons will not emit

    (C) Current will be very low

    (D) Explosion will occur

74. Work function for a metal depends on: [BSEB]

    (A) Intensity of light

    (B) Frequency of light

    (C) Nature of metal

    (D) Velocity of light

75. Photoelectric emission below threshold frequency: [BSEB]

    (A) Is very slow

    (B) Happens on increasing intensity

    (C) Is not possible

    (D) Happens only in vacuum

76. Most suitable metals for photoelectric emission are: [BSEB]

    (A) Hard metals

    (B) Alkali metals

    (C) Transition metals

    (D) Non-metals

77. Relation between work function $W$ and threshold frequency $\nu_0$ is: [BSEB]

    (A) $W = h\nu_0$

    (B) $W = h/\nu_0$

    (C) $W = \nu_0/h$

    (D) $W = hc/\nu_0$

78. Electron emission by ultraviolet light compared to visible light is: [BSEB]

    (A) Easier

    (B) Harder

    (C) Equal

    (D) Impossible

79. The value of ‘Quantum’ energy on increasing frequency: [BSEB]

    (A) Increases

    (B) Decreases

    (C) Remains unchanged

    (D) Becomes zero

80. Which unit is used more than Joule ($J$) for work function? [BSEB]

    (A) $\text{Watt}$

    (B) $\text{Newton}$

    (C) $\text{eV}$

    (D) $\text{Ampere}$

81. Threshold frequency is that frequency below which: [BSEB]

    (A) Current is maximum

    (B) No photoelectric emission occurs

    (C) Kinetic energy is maximum

    (D) None of these

82. Can copper show photoelectric effect with visible light? [BSEB]

    (A) Yes

    (B) No (Needs UV)

    (C) Only in dark

    (D) Only on heating

83. On polishing a metal surface, the work function: [BSEB]

    (A) Changes

    (B) Remains unchanged

    (C) Always increases

    (D) Becomes zero

84. Reason for minimum work function of Cesium (Cs): [BSEB]

    (A) It is solid

    (B) Its outer electrons are loosely bound

    (C) It is shiny

    (D) It is a gas

85. Rate of photo-electron emission depends on: [BSEB]

    (A) Intensity of incident light

    (B) Temperature of metal

    (C) Frequency of incident light

    (D) Both (A) and (C)

86. Number of electrons emitted in photoelectric effect is proportional to: [BSEB]

    (A) Frequency

    (B) Intensity of incident light

    (C) Wavelength

    (D) Work function

87. Is photoelectric emission an instantaneous process? [BSEB]

    (A) Yes (Less than $10^{-9}$ s)

    (B) No

    (C) Only at low intensity

    (D) Only at high temperature

88. To increase sensitivity of photo-cathode: [BSEB]

    (A) Metal with low work function is used

    (B) High work function is used

    (C) Glass is used

    (D) None of these

89. For alkali metals, threshold frequency falls in which region? [BSEB]

    (A) Ultraviolet region

    (B) Visible light region

    (C) Infrared region

    (D) X-ray region

90. The value of ‘Time lag’ in photoelectric emission is approximately: [BSEB]

    (A) $1 \text{ s}$

    (B) $10^{-3} \text{ s}$

    (C) $10^{-9} \text{ s}$

    (D) Zero

Part 4: Einstein’s Equation & Kinetic Energy

91. In explanation of photoelectric effect, light is considered as: [BSEB, 2022]

    (A) Wave

    (B) Particle (Photon)

    (C) Both

    (D) None

92. For which work was Einstein awarded the Nobel Prize? [BSEB]

    (A) Theory of Relativity

    (B) Explanation of Photoelectric Effect

    (C) Mass-energy relation

    (D) Brownian motion

93. Maximum kinetic energy of emitted electrons depends on: [BSEB, 2012]

    (A) Intensity

    (B) Frequency of incident light

    (C) Work function only

    (D) Both intensity and frequency

94. Einstein’s photoelectric equation is: [BSEB]

    (A) $K_{\max} = h\nu – \phi_0$

    (B) $K_{\max} = h\nu + \phi_0$

    (C) $h\nu = K_{\max} / \phi_0$

    (D) $E = mc^2$

95. Photoelectric current at stopping potential ($V_0$) is: [BSEB]

    (A) Maximum

    (B) Zero

    (C) Saturated

    (D) Minimum

96. On increasing intensity of incident light, stopping potential: [BSEB]

    (A) Increases

    (B) Decreases

    (C) Remains unchanged

    (D) Doubles

97. Relation between maximum velocity $v$ and stopping potential $V_0$ is: [BSEB]

    (A) $\frac{1}{2}mv^2 = eV_0$

    (B) $mv = eV_0$

    (C) $v = eV_0$

    (D) $v^2 = e/V_0$

98. Who first discovered photoelectric effect? [BSEB, 2017]

    (A) Einstein

    (B) Hertz

    (C) Lenard

    (D) Hallwachs

99. Energy of photo-electron depends on: [BSEB, 2017]

    (A) Intensity

    (B) Wavelength

    (C) Velocity of light

    (D) Time

100. Photoelectric current is maximum when anode potential is called: [BSEB]

     (A) Stopping potential

     (B) Saturated Potential

     (C) Zero potential

     (D) Threshold potential

101. Einstein’s equation is based on which conservation law? [BSEB]

     (A) Momentum conservation

     (B) Energy conservation

     (C) Charge conservation

     (D) Mass conservation

102. If frequency $\nu$ is doubled, maximum kinetic energy: [BSEB]

     (A) Will double

     (B) Will be more than double

     (C) Will remain unchanged

     (D) Will be half

103. Slope of graph between stopping potential and frequency is: [BSEB]

     (A) $h/e$

     (B) $e/h$

     (C) $h$

     (D) $e$

104. Photoelectric cell: [BSEB]

     (A) Converts electricity to light

     (B) Converts light to electricity

     (C) Converts heat to light

     (D) Converts magnetism to electricity

105. Photoelectric current is proportional to: [BSEB]

     (A) Frequency

     (B) Intensity of light

     (C) Wavelength

     (D) Stopping potential

106. If intensity of light is doubled, saturated current will be: [BSEB]

     (A) Half

     (B) Double

     (C) Four times

     (D) Unchanged

107. Maximum velocity of emitted electron becomes 2 times when frequency is doubled. Work function is: [BSEB, 2026]

     (A) $2h\nu/3$

     (B) $h\nu/3$

     (C) Zero

     (D) $h\nu/2$

108. Where is photo-cell used? [BSEB]

     (A) Burglar alarm

     (B) Sound production in cinema

     (C) Measuring intensity of light

     (D) All of the above

109. Stopping potential ($V_0$) depends on: [BSEB]

     (A) Frequency only

     (B) Nature of metal only

     (C) Both frequency and nature of metal

     (D) Intensity

110. Rate of photoelectric emission does not depend on: [BSEB]

     (A) Intensity

     (B) Time

     (C) Material of cathode

     (D) Frequency (above threshold)

111. Saturated current depends on which quantity of incident light? [BSEB]

     (A) Frequency

     (B) Intensity

     (C) Velocity

     (D) None of these

112. Is stopping potential negative? [BSEB]

     (A) Yes (Negative potential applied at anode)

     (B) No

     (C) Always zero

     (D) Positive

113. Why couldn’t wave theory explain photoelectric effect? [BSEB]

     (A) Due to time lag

     (B) Presence of threshold frequency

     (C) Kinetic energy not depending on intensity

     (D) All of the above

114. Anode used in photo-cell is: [BSEB]

     (A) Thick copper wire

     (B) Thin wire (so light isn’t blocked)

     (C) Iron plate

     (D) Silver layer

115. In Hertz’s experiment, how were EM waves detected? [BSEB]

     (A) By Sparking

     (B) By Sound

     (C) By glowing bulb

     (D) By moving needle

116. What did Hallwachs and Lenard find? [BSEB]

     (A) Emission of negatively charged particles

     (B) Emission of positively charged particles

     (C) Emission of neutrons

     (D) No emission

117. After saturation current, on increasing potential, current: [BSEB]

     (A) Increases

     (B) Decreases

     (C) Remains constant

     (D) Becomes zero

118. What does ‘$\phi_0$‘ represent in Einstein’s equation? [BSEB]

     (A) Velocity

     (B) Work-function

     (C) Momentum

     (D) Frequency

119. Can one photon emit more than one electron? [BSEB]

     (A) Yes

     (B) No (One photon – one electron)

     (C) Only at high intensity

     (D) Only in gases

120. Solar cell is based on which effect? [BSEB]

     (A) Magnetic effect

     (B) Photoelectric effect

     (C) Thermal effect

     (D) Chemical effect

Part 5: De-Broglie Matter Waves & Davisson-Germer Experiment

121. Formula for de-Broglie wavelength ($\lambda$) is: [BSEB, 2024]

     (A) $\lambda = hmv$

     (B) $\lambda = h/mv$

     (C) $\lambda = mc^2/h$

     (D) $\lambda = h\nu$

122. Ratio of de-Broglie wavelength associated with two electrons accelerated through 49 V and 64 V is: [BSEB, 2026]

     (A) 49/64

     (B) 64/49

     (C) 7/8

     (D) 8/7

123. Proponent of Matter Wave theory was: [BSEB]

     (A) De-Broglie

     (B) Huygens

     (C) Newton

     (D) Maxwell

124. For a particle of mass $m$ and charge $q$ accelerated by potential $V$, $\lambda$ will be: [BSEB, 2018]

     (A) $h/\sqrt{2mV}$

     (B) $q/\sqrt{2mV}$

     (C) $h/\sqrt{2mqV}$

     (D) $h/V$

125. Which nature of electron was verified by Davisson-Germer experiment? [BSEB]

     (A) Particle nature

     (B) Wave nature

     (C) Charged nature

     (D) None

126. What is same for an electron and a photon of same wavelength? [BSEB, 2023]

     (A) Velocity

     (B) Energy

     (C) Momentum ($p$)

     (D) Angular momentum

127. de-Broglie wavelength does not depend on: [BSEB, 2025]

     (A) Mass

     (B) Velocity

     (C) Charge

     (D) Momentum

128. Electron microscope works on which principle? [BSEB]

     (A) Refraction of light

     (B) Photoelectric effect

     (C) Wave nature of electron

     (D) Magnetic effect

129. Value of $\lambda$ in $\text{\AA}$ for electron accelerated through $V$ potential: [BSEB, 2017]

     (A) $12.27/\sqrt{V}$

     (B) $15/\sqrt{V}$

     (C) $100/V$

     (D) $1.22/V$

130. Why is wave nature of heavy particles (like cricket ball) not visible? [BSEB]

     (A) Velocity is very low

     (B) Wavelength is extremely small (negligible)

     (C) They are not charged

     (D) None

131. What are matter waves? [BSEB]

     (A) EM waves

     (B) Sound waves

     (C) Waves associated with moving particles

     (D) Light waves

132. Can matter waves travel in vacuum? [BSEB]

     (A) Yes

     (B) No

     (C) Only at high temp

     (D) Only in gases

133. Where is wave property of electron used? [BSEB]

     (A) In electron microscope

     (B) In radio

     (C) In television

     (D) In X-ray tube

134. Graph of $\lambda \propto 1/p$ is: [BSEB]

     (A) Straight line

     (B) Rectangular Hyperbola

     (C) Circle

     (D) Parabola

135. Crystal used in Davisson-Germer experiment was: [BSEB]

     (A) Diamond

     (B) Quartz

     (C) Nickel crystal

     (D) Rock salt

136. Relation between de-Broglie wavelength $\lambda$ and kinetic energy $K$ is: [BSEB]

     (A) $\lambda = h/\sqrt{2mK}$

     (B) $\lambda = h/2mK$

     (C) $\lambda = \sqrt{2mK}/h$

     (D) $\lambda = hK$

137. In explaining Bohr’s atomic model, what did de-Broglie assume? [BSEB]

     (A) Electron is a particle

     (B) Electron is a standing wave

     (C) Electron is stationary

     (D) None

138. Do both light photon and matter particle behave as wave? [BSEB]

     (A) Yes

     (B) No

     (C) Only photon

     (D) Only electron

139. What happens to electron beam in Davisson-Germer experiment? [BSEB]

     (A) Refraction

     (B) Diffraction

     (C) Reflection

     (D) Polarization

140. If velocity of electron is increased, $\lambda$: [BSEB]

     (A) Increases

     (B) Decreases

     (C) Remains constant

     (D) Becomes zero

141. $\lambda$ for electron accelerated by $100 \text{ V}$ will be: [BSEB]

     (A) $1.227 \text{ \AA}$

     (B) $12.27 \text{ \AA}$

     (C) $0.122 \text{ \AA}$

     (D) $1 \text{ \AA}$

142. Velocity of matter waves compared to velocity of light is: [BSEB]

     (A) Equal

     (B) More

     (C) Less

     (D) Much more

143. Are matter waves electromagnetic waves of charged particles? [BSEB]

     (A) Yes

     (B) No

     (C) Only for electron

     (D) Only for proton

144. Correct relation between momentum $p$ and $\lambda$ is: [BSEB, 2022]

     (A) $p = h\lambda$

     (B) $p = h/\lambda$

     (C) $p = \lambda/h$

     (D) $p = h^2\lambda$

145. If momentum of photon and electron is same, whose energy will be more? [BSEB]

     (A) Photon

     (B) Electron

     (C) Both same

     (D) Depends on mass

146. When is de-Broglie wavelength $\lambda$ zero? [BSEB]

     (A) When $v = c$

     (B) When $v$ is infinite

     (C) When $v = 0$

     (D) Never

147. At scattering angle $50^\circ$, when is diffraction maximum from Nickel crystal? [BSEB]

     (A) at $40 \text{ V}$

     (B) at $54 \text{ V}$

     (C) at $60 \text{ V}$

     (D) at $100 \text{ V}$

148. Who first experimentally verified matter waves? [BSEB, 2021]

     (A) de-Broglie

     (B) Davisson and Germer

     (C) Einstein

     (D) Bohr

149. On halving the velocity of a particle, its $\lambda$: [BSEB]

     (A) Will be half

     (B) Will double

     (C) Will be four times

     (D) Unchanged

150. According to modern physics, nature of matter is: [BSEB]

     (A) Particle only

     (B) Wave only

     (C) Dual

     (D) None of these