For a metal of work function \(6.6\) eV, which of the following wavelengths of incident radiation does not give rise to the photoelectric effect?
(take Planck's constant as \(6.6\times 10^{-34}\) J-s)
1. \(200~\text{nm}\)
2. \(150~\text{nm}\)
3. \(100~\text{nm}\)
4. \(50~\text{nm}\)
Subtopic:  Photoelectric Effect: Experiment |
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Level 2: 60%+
NEET - 2026
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Match List-I with List-II:
List-I List-II
\(\mathrm{(A)}\) \(E = h\nu\) \(\mathrm{(I)}\) de-Broglie wavelength
\(\mathrm{(B)}\) Diffraction and Interference \(\mathrm{(II)}\) Particle nature of light
\(\mathrm{(C)}\) \(\lambda = h/p\) \(\mathrm{(III)}\) Wave nature of light
\(\mathrm{(D)}\) Compton effect \(\mathrm{(IV)}\) Energy of photon
Choose the correct answer from the options given below:
1. \(\mathrm{A\text-IV, B\text-III, C\text-I, D\text-II}\)
2. \(\mathrm{A\text-I, B\text-IV, C\text-III, D\text-II}\)
3. \(\mathrm{A\text-IV, B\text-I, C\text-II, D\text-III}\)
4. \(\mathrm{A\text-IV, B\text-III, C\text-II, D\text-I}\)
Subtopic:  Particle Nature of Light |
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Level 2: 60%+
NEET - 2026
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A ray of light with wavelength \(\lambda\) is incident on three different photo-electric cells namely \(1,\) \(2\) and \(3.\) The threshold wavelength of these photo-electric cells are \(\lambda_1\), \(\lambda_2\), and \(\lambda_3\), respectively and the magnitude of stopping potentials of these cells are \(V_1, ~V_2 \), and \(V_3,\) respectively. The relation between \(\lambda\) and threshold wavelengths are \(\lambda_1 < \lambda_, \) \(\lambda_2>\lambda\) and \(\lambda_3>>\lambda.\) The correct option is:
1. \(V_1<V_2,~V_3=0\)
2. \(V_1=0,~V_2<V_3\)
3. \(V_1=0,~V_2>V_3\)
4. \(V_1>V_2,~V_3=0\)
Subtopic:  Photoelectric Effect: Experiment |
Level 3: 35%-60%
NEET - 2026
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A beam of light falls on a metal surface such that photo-electrons are generated. If the power of the light source starts to decrease linearly with time \(t,\) then the variation of the photocurrent \(I\) and magnitude of the stopping potential \(|V|\) with time is best represented by:
1.
2.
3.
4.
Subtopic:  Photoelectric Effect: Experiment |
 53%
Level 3: 35%-60%
NEET - 2026
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A photon and an electron, each of \(20~\text{eV}\) energy, move in free space. The ratio of the linear momentum of electron \(p_\mathrm{e}\) to that of photon \(p_\mathrm{ph},\) \(\dfrac {p_\mathrm{e}}{p_\mathrm{ph}}\)is:
(take speed of light \(=3\times10^8~\text{ms}^{-1}, \) charge of electron \(=-1.6\times 10^{-19}~\text{C}\) and mass of electron \(=9 \times 10^{-31}~\text{kg}\))
1. \(275\) 2. \(\dfrac {2 } {450}\)
3. \(\dfrac {1} {250}\) 4. \(225\)
Subtopic:  Particle Nature of Light |
Level 4: Below 35%
NEET - 2026
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A photon and an electron (of mass \(m\)) have the same total energy \(E. \) If \(c\) denotes the speed of light, what is the ratio of their de-Broglie wavelengths \((\lambda_{\text{photon}}/\lambda_{\text{electron}})\text{?} \)

1. \(c\sqrt{\dfrac{2m}{E}} \) 2. \(\dfrac{1}{c}\sqrt{\dfrac{E}{2m}}\)
3. \(\sqrt{\dfrac{E}{2m}}\) 4. \(c\sqrt{2mE}\)
Subtopic:  De-broglie Wavelength |
Level 3: 35%-60%
NEET - 2025
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Which of the following options represents the variation of photoelectric current with the property of light shown on the \(x \text{-}\)axis?
(A) (B)
(C) (D)
 
1. (A) and (D) 2. (B) and (D)
3. (A) only 4. (A) and (C)
Subtopic:  Photoelectric Effect: Experiment |
 51%
Level 3: 35%-60%
NEET - 2025
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De-Broglie wavelength of an electron orbiting in the \(n=2\) state of a hydrogen atom is close to: (given: Bohr radius \(=0.052~ \text{nm}\))
1. \(1.67~ \text{nm}\) 2. \(2.67~ \text{nm}\)
3. \(0.067~ \text{nm}\) 4. \(0.67~ \text{nm}\)
Subtopic:  De-broglie Wavelength |
Level 3: 35%-60%
NEET - 2025
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An electron and an alpha particle are accelerated by the same potential difference. Let \(\lambda_\mathrm{e}\) and \(\lambda_\mathrm{\alpha}\) denote the de-Broglie wavelengths of the electron and the alpha particle, respectively, then:
1. \(\lambda_{\mathrm{e}}>\lambda_{\alpha}\) 2. \(\lambda_{\mathrm{e}}=4\lambda_{\alpha}\)
3. \(\lambda_{\mathrm{e}}=\lambda_{\alpha}\) 4. \(\lambda_{\mathrm{e}}<\lambda_{\alpha}\)
Subtopic:  De-broglie Wavelength |
 71%
Level 2: 60%+
NEET - 2024
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Radiation of wavelength \(280~\text{nm}\) is used in an experiment of photoelectric effect with cathode of work function, \(2.5~\text{eV}.\) The maximum kinetic energy of the photoelectrons is:
(take \(h=6.62\times10^{-34}~\text{J s}\) and \(c=3\times10^{8}~\text{ms}^{-1}\))
1. \(4.4~\text{eV}\) 2. \(7.103\times10^{-15}~\text{J}\)
3. \(1.9~\text{eV}\) 4. \(4.60~\text{eV}\)
Subtopic:  Einstein's Photoelectric Equation |
 74%
Level 2: 60%+
NEET - 2024
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