JEE Questions for Physics Dual Nature Of Radiation And Matter Quiz 12 - MCQExams.com

In an X-rays tube, the intensity of the emitted X-rays beam is increased by
  • Increasing the filament current
  • Decreasing the filament current
  • Increasing the target potential
  • Decreasing the target potential
The binding energy of the innermost electron in tungsten is 40 keV. To produce characteristic X-rays using a tungsten target in an X-rays tube the potential difference V between the cathode and the anti-cathode should be
  • V < 40 kV
  • V ≤ 40 kV
  • V > 40 kV
  • V > /< 40 kV
In above question the energy of the characteristic X-rays given out is
  • Less than 40 keV
  • More than 40 keV
  • Equal to 40 keV
  • ≥ 40 keV
The wavelength of most energetic X-rays emitted when a metal target is bombarded by 40 keV electrons, is approximately
(h = 6.62 × 10–34 J-sec; 1 eV = 1.6 × 10–19 J; c = 3 × 108 m/s)
  • 300 Å
  • 10 Å
  • 4 Å
  • 0.31 Å
Compton effect shows that
  • X-rays are waves
  • X-rays have high energy
  • X-rays can penetrate matter
  • Photons have momentum
X-rays of λ =1 Å have frequency
  • 3 × 108 Hz
  • 3 × 1018 Hz
  • 3 × 1010 Hz
  • 3 × 1015 Hz
Mosley measured the frequency (f) of the characteristic X-rays from many metals of different atomic number (Z) and represented his results by a relation known as Mosley\'s law. This law is (a, b are constants)
  • f = a(Z – b)2
  • Z = a (f – b) 2
  • f2 = a (Z – b)
  • f = a (Z – b) 1/2
Penetrating power of X-rays depends on
  • Current flowing in the filament
  • Applied potential difference
  • Nature of the target
  • All of the above
The energy of a photon of characteristic X-rays from a Coolidge tube comes from
  • The kinetic energy of the striking electron
  • The kinetic energy of the free electrons of the target
  • The kinetic energy of the ions of the target
  • An electronic transition of the target atom
X-rays are produced in laboratory by
  • Radiation
  • Decomposition of the atom
  • Bombardment of high energy electron on heavy metal
  • None of the above
Bragg\'s equation will have no solution if
  • λ > 2d
  • λ < 2d
  • λ < d
  • λ = d
For harder X-rays
  • The wavelength is higher
  • The intensity is higher
  • The frequency is higher
  • The photon energy is lower
When cathode rays strike a metal target of high melting point with very high velocity, then
  • X-rays are produced
  • Alpha-rays are produced
  • UV waves are produced
  • Ultrasonic waves are produced
Kα characteristic X-ray refers to the transition
  • n = 2 to n = 1
  • n = 3 to n = 2
  • n = 3 to n = 1
  • n = 4 to n = 2
X-rays are produced in X-ray tube operating at a given accelerating voltage. The wavelength of the continuous X-rays has values from
  • 0 to ∞
  • λmin to ∞, where λmin > 0
  • 0 to λmax where λmax < ∞
  • λmin to λmax , where 0 < λmin < λmax < ∞
The wavelength of X-rays is
  • 2000 Å
  • 2 Å
  • 1 mm
  • 1 cm
The ratio of the energy of an X-ray photon of wavelength 1 Å to that of visible light of wavelength 5000 Å is
  • 1 : 5000
  • 5000 : 1
  • 1 : 25 ×106
  • 25 × 106
According to Mosley\'s law, the frequency of a spectral line in X-ray spectrum varies as
  • Atomic number of the element
  • Square of the atomic number of the element
  • Square root of the atomic number of the element
  • Fourth power of the atomic number of the element
What determines the hardness of the X-rays obtained from the Coolidge tube?
  • Current in the filament
  • Pressure of air in the tube
  • Nature of target
  • Potential difference between cathode and target
The most penetrating radiation out of the following is
  • X-rays
  • β-rays
  • α-particles
  • γ-rays
X-rays cannot be deflected by means of an ordinary grating due to
  • Large wavelength
  • High speed
  • Short wavelength
  • None of these
The energy of an X-ray photon of wavelength of 1.65 Å is
(h = 6.6 × 10–34 J-sec, c = 3 × 108ms–1. 1eV = 1.6 × 10–19J)
  • 3.5 keV
  • 5.5 keV
  • 7.5 keV
  • 9.5 keV
If λ = 10 Å, then it corresponds to
  • Infrared
  • Microwave
  • Ultraviolet
  • X-rays
Bragg\'s law for X-rays is
  • d sin θ = 2 nλ
  • 2d sin θ = nλ
  • n sin θ = 2λd
  • None of these
In an X-ray tube electrons bombarding the target produce X-rays of minimum wavelength 1 Å. What must be the energy of bombarding electrons?
  • 13375 eV
  • 12375 eV
  • 14375 eV
  • 15375 eV
According to Einstein\'s photoelectric equation, the plot of the kinetic energy of the emitted photo electrons from a metal versus the frequency, of the incident radiation gives a straight line whose slope
  • Is the same for all metals and independent of the intensity of the radiation
  • Depends on the intensity of the radiation
  • Depends both on the intensity of the radiation and the metal used
  • Depends on the nature of the metals used
If energy of K-shell electron is –40000 eV and if 60000 V potential is applied at coolidge tube then which of the following X-rays will form?
  • Continuous
  • White X-rays
  • Continuous and all series of characteristic
  • None of the above
For production of characteristic Kβ X-rays, the electron transition is
  • n = 2 to n = 1
  • n = 3 to n = 2
  • n = 3 to n = 1
  • n = 4 to n = 2
Penetrating power of X-rays does not depend on
  • Wavelength
  • Energy
  • Potential difference
  • Current in the filament
The potential difference applied to an X-ray tube is 5 kV and the current through it is 3.2 mA. Then the number of electrons striking the target per second is
  • 2 × 1016
  • 5 × 1016
  • 1 × 1017
  • 4 × 1015
For the production of characteristic Kγ X-rays, the electron transition is
  • n = 2 and n = 1
  • n = 3 to n = 2
  • n = 3 to n = 1
  • n = 4 to n = 1
If the potential difference applied across X-rays tube is V volts, then approximately minimum wavelength of the emitted X-rays will be

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  • 2)
    Physics-Dual Nature of Radiation and Matter-67917.png

  • Physics-Dual Nature of Radiation and Matter-67918.png

  • Physics-Dual Nature of Radiation and Matter-67919.png
X-ray will travel minimum distance in
  • Air
  • Iron
  • Wood
  • Water
X-rays are produced by accelerating electrons by voltage V and let they stike a metal of atomic number Z. The highest frequency of X-rays produced is proportional to
  • V
  • Z
  • (Z – 1)
  • (Z – 1)2
Which of the following supports the wave nature of X-rays?
  • Photoelectric effect
  • Photosynthesis
  • Compton scattering
  • Diffraction
A particle of mass M at rest decays into two particles of masses m1 and m2, having non-zero velocities. The ratio of the de-Broglie wavelengths of the particles, λ1 / λ2 is
  • m1 / m2
  • m2/ m1
  • 1.0

  • Physics-Dual Nature of Radiation and Matter-67922.png
A photon and an electron have equal energy E. λphoton / λelectron is proportional to

  • Physics-Dual Nature of Radiation and Matter-67924.png
  • 2)
    Physics-Dual Nature of Radiation and Matter-67925.png
  • 1 /E
  • Does not depend upon E
An image of the sun is formed by a lens of focal length of 30 cm on the metal surface of a photoelectric cell and a photoelectric current I is produced. The lens forming the image is then replaced by another of the same diameter but of focal length 15 cm. The photoelectric current in this case is
  • I /2
  • I
  • 2I
  • 4I
When an inert gas is filled in place of vacuum in a photo cell, then
  • Photo-electric current is decreased
  • Photo-electric current is increased
  • Photo-electric current remains the same
  • Decrease or increase in photo-electric current does not depend upon the gas filled
When a point source of monochromatic light is at a distance of 0.2 m from a photoelectric cell, the cut-off voltage and the saturation current are 0.6 volt and 18 mA respectively. If the same source is placed 0.6 m away from the photoelectric cell, then
  • The stopping potential will be 0.2 V
  • The stopping potential will be 0.6 V
  • The saturation current will be 6 mA
  • The saturation current will be 18 mA
Ultraviolet light of wavelength 300 nm and intensity 1.0 watt/m2 falls on the surface of a photosensitive material. If 1% of the incident photons produce photoelectrons, then the number of photoelectrons emitted from an area of 1.0 cm2 of the surface is nearly
  • 9.61 × 1014 per sec
  • 4.12 × 1013 per sec
  • 1.51 × 1012 per sec
  • 2.13 × 1011 per sec
Photoelectric emission is observed from a metallic surface for frequencies v1 and v2 of the incident light rays (v1 > v2). If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of 1 : k, then the threshold frequency of the metallic surface is

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  • 2)
    Physics-Dual Nature of Radiation and Matter-67931.png

  • Physics-Dual Nature of Radiation and Matter-67932.png

  • Physics-Dual Nature of Radiation and Matter-67933.png
Light from a hydrogen discharge tube is incident on the cathode of a photoelectric cell the work function of the cathode surface is 4.2 eV. In order to reduce the photocurrent to zero the voltage of the anode relative to the cathode must be made
  • –4.2 V
  • –9.4 V
  • –17.8 V
  • +9.4 V
The largest distance between the interatomic planes of a crystal is 10–7 cm. The upper limit for the wavelength of X-rays which can be usefully studied with this crystal is
  • 1 Å
  • 2 Å
  • 10 Å
  • 20 Å
The velocity, v, at which the mass of a particle is double its rest mass is

  • Physics-Dual Nature of Radiation and Matter-67937.png
  • 2)
    Physics-Dual Nature of Radiation and Matter-67938.png

  • Physics-Dual Nature of Radiation and Matter-67939.png

  • Physics-Dual Nature of Radiation and Matter-67940.png
The wavelength of Kα X-rays produced by an X-ray tube is 0.76 Å. The atomic number of the anode material of the tube is
  • 20
  • 60
  • 40
  • 80
X-ray beam of intensity I0 passes through an absorption plate of thickness d. If absorption coefficient of material of plate is µ, the correct statement regarding the transmitted intensity I of X-ray is
  • I = I0(1 – e–µd)
  • I = I0 e–µd
  • I = I0(1 – e–µ/d)
  • I = I0 e–µ/d)
The Kα X-ray emission line of tungsten occurs λ = 0.021 nm. The energy difference between K and L levels in this atom is about
  • 0.51 MeV
  • 1.2 MeV
  • 59 KeV
  • 13.6 eV
Electrons with energy 80 keV are incident on the tungsten target of an X-ray tube. K shell electrons of tungsten have ionization energy 72.5 keV. X-rays emitted by the tube contain only
  • A continuous X-ray spectrum (Bremsstrahlung) with a minimum wavelength of - 0.155 A
  • A continuous X-ray spectrum (Bremsstrahlung) with all wavelengths
  • The characteristic X-rays spectrum of tungsten
  • A continuous X-ray spectrum (Bremsstrahlung) with a minimum wavelength of - 0.155 A and the characteristic X-ray spectrum of tungsten
The X-ray wavelength of Lα line of platinum (Z =is 1.30 Å. The X-ray wavelength of Lα line of Molybdenum (Z =is
  • 5.41 Å
  • 4.20 Å
  • 2.70 Å
  • 1.35 Å
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