If $$c$$ is the velocity of light in free space, the correct statements about photon among the following are:
 A. The energy of a photon is $$E=h\nu.$$ B. The velocity of a photon is $$c.$$ C. The momentum of a photon, $$p={\dfrac{h\nu}{c}}.$$ D. In a photon-electron collision, both total energy and total momentum are conserved. E. Photon possesses positive charge.
Choose the correct answer from the options given below:
1. $$\text {A, B, C}$$ and $$\text {D}$$ only
2. $$\text {A, C}$$ and $$\text {D}$$ only
3. $$\text {A, B, D}$$ and $$\text {E}$$ only
4. $$\text {A}$$ and $$\text {B}$$ only
Subtopic: Â Particle Nature of Light |
Â 58%
From NCERT
NEET - 2024
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The graph which shows the variation of $$\bigg({\dfrac{1}{\lambda^2}}\bigg)$$ and its kinetic energy, $$E$$ is (where $$\lambda$$ is de-Broglie wavelength of a free particle):
 1 2 3 4
Subtopic: Â De-broglie Wavelength |
Â 55%
From NCERT
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: Â Einstein's Photoelectric Equation |
Â 73%
From NCERT
NEET - 2024
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Given below are two statements:
 Statement I: The de Broglie wavelength associated with a material particle depends on its charge and nature. Statement II: The wave nature of particles in sub-atomic domain is significant and measurable.

In the light of the above statements, choose the most appropriate answer from the options given below:
 1 Both Statement I and Statement II are correct. 2 Both Statement I and Statement II are incorrect. 3 Statement I is correct but Statement II is incorrect. 4 Statement I is incorrect but Statement II is correct.
Subtopic: Â De-broglie Wavelength |
From NCERT
NEET - 2024
Hints

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: Â De-broglie Wavelength |
Â 69%
From NCERT
NEET - 2024
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If $$\phi$$ is the work function of photosensitive material in $$\text{eV}$$ and light of wavelength of numerical value $$\lambda=\frac{{hc}}{{e}}$$ metre, is incident on it with energy above its threshold value at an instant then the maximum kinetic energy of the photo-electron ejected by it at that instant (Take $$h$$-Plank's constant, $$c$$-velocity of light in free space) is (in SI units):
1. $${e}+2\phi$$
2. $$2{e}-\phi$$
3. $${e}-\phi$$
4. $${e}+\phi$$
Subtopic: Â Einstein's Photoelectric Equation |
Â 75%
From NCERT
NEET - 2024
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The work functions of Caesium $$(\mathrm{Cs})$$, Potassium $$(\mathrm{K})$$ and Sodium $$(\mathrm{Na})$$ are $$2.14~\text{eV}$$, $$2.30~\text{eV}$$ and $$2.75~\text{eV}$$ respectively. If incident electromagnetic radiation has an incident energy of $$2.20~\text{eV}$$. which of these photosensitive surfaces may emit photoelectrons?
 1 $$\mathrm{Na}$$ only 2 $$\mathrm{Cs}$$ only 3 Both $$\mathrm{Na}$$ and $$\mathrm{K}$$ 4 $$\mathrm{K}$$ only
Subtopic: Â Photoelectric Effect: Experiment |
Â 65%
From NCERT
NEET - 2023
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The de Broglie wavelength associated with an electron, accelerated by a potential difference of $$81$$ V is given by:
1. $$13.6$$ nm
2. $$136$$ nm
3. $$1.36$$ nm
4. $$0.136$$ nm
Subtopic: Â De-broglie Wavelength |
Â 54%
From NCERT
NEET - 2023
Hints

The maximum kinetic energy of the emitted photoelectrons in photoelectric effect is independent of:
 1 work function of material 2 intensity of incident radiation 3 frequency of incident radiation 4 wavelength of incident radiation
Subtopic: Â Photoelectric Effect: Experiment |
Â 76%
From NCERT
NEET - 2023
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When two monochromatic lights of frequency, $$\nu$$ and $$\dfrac{\nu}{2}$$ are incident on a photoelectric metal, their stopping potential becomes $$\dfrac{V_{s}}{2}$$ and $$V_s$$, respectively. The threshold frequency for this metal is:
 1 $$\dfrac{3}{2} \nu$$ 2 $$2\nu$$ 3 $$3\nu$$ 4 $$\dfrac{2}{3} \nu$$