Dual Nature of Radiation and Matter
76 Board Physics previous year questions on Dual Nature of Radiation and Matter — options free on every question; 8 include the answer & explanation free, the rest unlock with PYQ Pass.
The waves associated with a moving electron and a moving proton have the same wavelength \(\lambda\). It implies that they have the same :
momentum
de brogle wavelength is given by
\(\lambda =\frac{\mathrm{h}}{\mathrm{p}}\\ \mathrm{here},\mathrm{wavelength}\mathrm{is}\mathrm{same}\mathrm{for}\mathrm{electron}\mathrm{and}\mathrm{proton},\\ \mathrm{so}\mathrm{the}\mathrm{momentum}\mathrm{is}\mathrm{also}\mathrm{same}\mathrm{for}\mathrm{eletron}\mathrm{and}\mathrm{proton}.\)
A source produces monochromatic light of frequency \(5.0\times {10}^{14}Hz\) and the power emitted is 3.31 mW. The number of photons emitted per second by the source, on an average is
\({10}^{16}\)
The energy of a single photon is given by the formula \(E=h\nu\) ,where \(h\) is Planck's constant. The value of Planck's constant is
\(h=6.626\times10^{-34}J\cdot s\).
\( E=(6.626\times10^{-34}J\cdot s)(5.0\times10^{14}Hz) \)
\( E=3.313\times10^{-19}J \)
Step 3: Calculate the number of photons emitted per second
The number of photons emitted per second, N, is the total power divided by the energy of a single photon.
\( N=\frac{P}{E} \)
\( N=\frac{3.31\times10^{-3}W}{3.313\times10^{-19}J} \)
\(N\approx9.99\times10^{15}\text{ photons/s} \)
A source produces monochromatic light of frequency \(5.0\times {10}^{14}Hz\) and the power emitted is 3.31 mW. The number of photons emitted per second by the source, on an average is
\({10}^{16}\)
The energy of a single photon is given by the formula \(E=h\nu\) ,where \(h\) is Planck's constant. The value of Planck's constant is
\(h=6.626\times10^{-34}J\cdot s\).
\( E=(6.626\times10^{-34}J\cdot s)(5.0\times10^{14}Hz) \)
\( E=3.313\times10^{-19}J \)
Step 3: Calculate the number of photons emitted per second
The number of photons emitted per second, N, is the total power divided by the energy of a single photon.
\( N=\frac{P}{E} \)
\( N=\frac{3.31\times10^{-3}W}{3.313\times10^{-19}J} \)
\(N\approx9.99\times10^{15}\text{ photons/s} \)
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
\({\lambda }_{e}>{\lambda }_{p}>{\lambda }_{d}\)
Wavelengths associated with an electron ( \(\lambda_e\) ), proton ( \(\lambda_p\) ), and deuteron ( \(\lambda_d\) ), all moving with the same speed.
Using de Broglie's equation: \(\boldsymbol{\lambda}=\frac{\boldsymbol{h}}{\boldsymbol{m} v}\)
- Since all particles have the same speed (v), their wavelengths are inversely proportional to their masses.
- Electron has the smallest mass, so it has the longest wavelength.
- Deuteron has the highest mass, so it has the shortest wavelength.
Mass relation: \(m_e
wavelength relation: \(\lambda_e>\lambda_p>\lambda_d\)
The relation between energy E and momentum p of a photon is
(Shift - II Memory based)
E = p c
Momentum is given by
\(\mathrm{p}=\frac{\mathrm{E}}{\mathrm{c}}\\ \mathrm{So},\\ \mathrm{E}=\mathrm{p}\mathrm{c}\)
In photoelectric effect an EM-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is 2.14 eV and stopping potential is 2 V , what is the wavelength of the EM-wave ?
(Given \(\mathrm{hc}=1242\mathrm{eVnm}\) where h is the Planck's constant and c is the speed of light in vaccum.)
[JEE Main 2025, 23 Jan (Shift 2)]
300 nm
\(K\cdot E=e{V}_{s}\\ =2eV\\ K\cdot E\cdot =E-∅\\ 2=E-2.14\\ E=4.14eV\\ \frac{hc}{\lambda }=E\\ \frac{1242}{\lambda }=4.14\)
\(\lambda =300nm\)
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
\(\frac{1}{3}\)
$$\begin{aligned}& \text{Given: photon energies } h\nu_A=3.3\ \mathrm{eV},\; h\nu_B=11.3\ \mathrm{eV},\; \text{work function } \phi=2.3\ \mathrm{eV}. \\[4pt]& \text{Maximum kinetic energy of emitted electrons: } K_{\max}=h\nu-\phi. \\[4pt]& K_{A}=3.3-2.3=1.0\ \mathrm{eV}, \qquad K_{B}=11.3-2.3=9.0\ \mathrm{eV}. \\[6pt]& \text{Since } K=\tfrac{1}{2}mv^2 \Rightarrow v\propto\sqrt{K}, \\[4pt]& \therefore\; \dfrac{v_A}{v_B}=\sqrt{\dfrac{K_A}{K_B}}=\sqrt{\dfrac{1.0}{9.0}}=\dfrac{1}{3}. \\[8pt]& \boxed{\dfrac{v_A}{v_B}=\dfrac{1}{3}}\end{aligned}$$
If E, p, m and c denote the energy, linear momentum, mass and speed of light, then the equation representing the correct relation could be
(Shift - II Memory based)
\(E^2=p^2 c^2+m^2 c^4\)
\(\mathrm{In}\mathrm{relativistic}\mathrm{case}\\ \mathrm{m}=\frac{{\mathrm{m}}_{\mathrm{o}}}{\sqrt{1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}}}\\ {\mathrm{p}}^{2}=\frac{{\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{v}}^{2}}{\left(1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}\right)}=\frac{{\mathrm{m}}_{\mathrm{o}}^{2}\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}{\mathrm{c}}^{2}}{\left(1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}\right)}\\ {\mathrm{p}}^{2}=\frac{{\mathrm{m}}_{\mathrm{o}}^{2}\left(\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}-1+1\right){\mathrm{c}}^{2}}{\left(1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}\right)}={\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{c}}^{2}+\frac{{\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{c}}^{2}}{\left(1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}\right)}\\ {\mathrm{p}}^{2}{\mathrm{c}}^{2}={\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{c}}^{2}+\left(\frac{{\mathrm{m}}_{\mathrm{o}}}{\sqrt{\left(1-\frac{{\mathrm{v}}^{2}}{{\mathrm{c}}^{2}}\right)}}\right){\mathrm{c}}^{4}\\ {\mathrm{p}}^{2}{\mathrm{c}}^{2}=-{\left({\mathrm{m}}_{\mathrm{o}}{\mathrm{c}}^{2}\right)}^{2}+{\left({\mathrm{mc}}^{2}\right)}^{2}\\ {\left({\mathrm{mc}}^{2}\right)}^{2}={\mathrm{p}}^{2}{\mathrm{c}}^{2}+{\left({\mathrm{m}}_{\mathrm{o}}{\mathrm{c}}^{2}\right)}^{2}\\ {\mathrm{E}}^{2}={\mathrm{p}}^{2}{\mathrm{c}}^{2}+\left({\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{c}}^{4}\right)\\ \mathrm{E}=\sqrt{{\mathrm{p}}^{2}{\mathrm{c}}^{2}+\left({\mathrm{m}}_{\mathrm{o}}^{2}{\mathrm{c}}^{4}\right)}\\\)
A source produces monochromatic light of frequency \(5.0\times {10}^{14}Hz\) and the power emitted is 3.31 mW. The number of photons emitted per second by the source, on an average is
Options are free to see. Unlock the correct answer and full explanation with Pass.
The quantum nature of light explains the observations on photoelectric effect as -
Options are free to see. Unlock the correct answer and full explanation with Pass.
The quantum nature of light explains the observations on photoelectric effect as -
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The waves associated with a moving electron and a moving proton have the same wavelength \(\lambda\). It implies that they have the same :
Options are free to see. Unlock the correct answer and full explanation with Pass.
When a metal surface is illuminated by a wavelength \(\lambda\), the maximum kinetic energy of the ejected electrons is \(2\text{ }\text{eV}\). If the metal is illuminated by a wavelength \(\lambda \mathrm{/}2\), what will be the maximum kinetic energy? (Work function \(ϕ=1\text{ }\text{eV}\))
(Shift II Memory Based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
Photons of energy \(3.2 \mathrm{eV}\) are incident on a photosensitive surface. If the stopping potential for the emitted electrons is \(1.5 \mathrm{~V}\), the work function for the surface is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (\(\text{Cs}\)) and lithium (\(\text{Li}\)) metals are \(1.9\text{ }\text{eV}\) and \(2.5\text{ }\text{eV}\), respectively. If light of wavelength 550 nm is incident on these two metal surfaces, for which metal(s) will the photoelectric effect occur? (Planck’s constant \(h=6.63\times 1{0}^{−34}\text{ }\text{Js}\), Speed of light \(c=3\times 1{0}^{8}\text{ }\text{m/s}\).)
[JEE Main 2025, 22 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
A light of wavelength ‘λ’ is incident on a metal having work function φ = 3.4 eV. The stopping potential measured for the photoelectric current setup is 1.6 eV. Find the value of λ [hc = 12400 eV Å]
(Shift - II Memory Based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
A proton and an alpha particle have the same kinetic energy. The ratio of de Broglie wavelengths associated with the proton to that with the alpha particle is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work function for a photosensitive surface is 3·315 eV. The cut-off wavelength for photoemission of electrons from this surface is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
A photo-emissive substance is illuminated with a radiation of wavelength \({\lambda }_{\mathrm{i}}\) so that it releases electrons with de-Broglie wavelength \({\lambda }_{\mathrm{e}}\). The longest wavelength of radiation that can emit photoelectron is \({\lambda }_{0}\). Expression for de-Broglie wavelength is given by :
( m : mass of the electron, h : Planck's constant and c : speed of light)
Options are free to see. Unlock the correct answer and full explanation with Pass.
In an experiment with photoelectric effect, the stopping potential,
[JEE Main 2025, 29 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Emission of electrons in photoelectric effect can be suppressed by applying a sufficiently negative electron potential to the photoemissive substance.
Reason (R) : A negative electric potential, which stops the emission of electrons from the surface of a photoemissive substance, varies linearly with frequency of incident radiation.
In the light of the above statements, choose the most appropriate answer from the options given below :
[JEE Main 2025, 29 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
If E, p, m and c denote the energy, linear momentum, mass and speed of light, then the equation representing the correct relation could be
(Shift - II Memory based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
An electron of mass ' m ' with an initial velocity \(\vec{v}={v}_{0}\hat{i}\left({v}_{0}>0\right)\) enters an electric field \(\vec{E}=-{E}_{0}\hat{k}\). If the initial de Broglie wavelength is \({\lambda }_{0}\), the value after time t would be
[JEE Main 2025, 24 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work function for a photosensitive surface is 3·315 eV. The cut-off wavelength for photoemission of electrons from this surface is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work function for a photosensitive surface is 3·315 eV. The cut-off wavelength for photoemission of electrons from this surface is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (\(\text{Cs}\)) and lithium (\(\text{Li}\)) metals are \(1.9\text{ }\text{eV}\) and \(2.5\text{ }\text{eV}\), respectively. If light of wavelength 550 nm is incident on these two metal surfaces, for which metal(s) will the photoelectric effect occur? (Planck’s constant \(h=6.63\times 1{0}^{−34}\text{ }\text{Js}\), Speed of light \(c=3\times 1{0}^{8}\text{ }\text{m/s}\).)
[JEE Main 2025, 22 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (\(\text{Cs}\)) and lithium (\(\text{Li}\)) metals are \(1.9\text{ }\text{eV}\) and \(2.5\text{ }\text{eV}\), respectively. If light of wavelength 550 nm is incident on these two metal surfaces, for which metal(s) will the photoelectric effect occur? (Planck’s constant \(h=6.63\times 1{0}^{−34}\text{ }\text{Js}\), Speed of light \(c=3\times 1{0}^{8}\text{ }\text{m/s}\).)
[JEE Main 2025, 22 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The stopping potential \({\mathrm{V}}_{0}\) measured in a photoelectric experiment for a metal surface is plotted against frequency v of the incident radiation. Let m be the slope of the straight line so obtained. Then the value of charge of an electron is given by ( h is the Planck's constant.)
Options are free to see. Unlock the correct answer and full explanation with Pass.
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
Options are free to see. Unlock the correct answer and full explanation with Pass.
In photoelectric effect an EM-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is 2.14 eV and stopping potential is 2 V , what is the wavelength of the EM-wave ?
(Given \(\mathrm{hc}=1242\mathrm{eVnm}\) where h is the Planck's constant and c is the speed of light in vaccum.)
[JEE Main 2025, 23 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
A metal target with atomic number Z = 46 is bombarded with a high energy electron beam. The emission of X-rays from the target is analyzed. The ratio r of the wavelengths of the Kα-line and the cut-off is found to be r = 2. If the same electron beam bombards another metal target with Z = 41 , the value of r will be
Options are free to see. Unlock the correct answer and full explanation with Pass.
The stopping potential \({\mathrm{V}}_{0}\) measured in a photoelectric experiment for a metal surface is plotted against frequency v of the incident radiation. Let m be the slope of the straight line so obtained. Then the value of charge of an electron is given by ( h is the Planck's constant.)
Options are free to see. Unlock the correct answer and full explanation with Pass.
A sub-atomic particle of mass \({10}^{-30}\mathrm{kg}\) is moving with a velocity \(2.21\times {10}^{6}\mathrm{m}/\mathrm{s}\). Under the matter wave consideration, the particle will behave closely like ____ .\(\left(\mathrm{h}=6.63\times {10}^{-34}\mathrm{J}.\mathrm{s}\right)\)
[JEE Main 2025, 23 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The quantum nature of light explains the observations on photoelectric effect as -
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
An electron and an alpha particle are accelerated by the same potential difference. Let \({\lambda }_{e}\) and \({\lambda }_{\alpha }\) denote the de Broglie wavelengths of the electron and the alpha particle, respectively, then:
[Re-NEET 2024]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The waves associated with a moving electron and a moving proton have the same wavelength \(\lambda\). It implies that they have the same :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The quantum nature of light explains the observations on photoelectric effect as -
Options are free to see. Unlock the correct answer and full explanation with Pass.
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Emission of electrons in photoelectric effect can be suppressed by applying a sufficiently negative electron potential to the photoemissive substance.
Reason (R) : A negative electric potential, which stops the emission of electrons from the surface of a photoemissive substance, varies linearly with frequency of incident radiation.
In the light of the above statements, choose the most appropriate answer from the options given below :
[JEE Main 2025, 29 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two beams, A and B whose photon energies are 3.3 eV and 11.3 eV respectively, illuminate a metallic surface (work function 2.3 eV ) successively. The ratio of maximum speed of electrons emitted due to beam \(A\) to that due to beam \(B\) is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
The stopping potential \({\mathrm{V}}_{0}\) measured in a photoelectric experiment for a metal surface is plotted against frequency v of the incident radiation. Let m be the slope of the straight line so obtained. Then the value of charge of an electron is given by ( h is the Planck's constant.)
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (Cs) and lithium (Li) metals are 1.9 eV and 2.5 eV , respectively. If we incident a light of wavelength 550 nm on these two metal surfaces, then photo-electric effect is possible for the case of
Options are free to see. Unlock the correct answer and full explanation with Pass.
A proton of mass '\({m}_{p}\)' has same energy as that of a photon of wavelength '\(\lambda\)'. If the proton is moving at non-relativistic speed, then ratio of its de Broglie wavelength to the wavelength of photon is.
[JEE Main 2025, 28 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
Options are free to see. Unlock the correct answer and full explanation with Pass.
A proton of mass \({m}_{p}\) has the same energy as that of a photon with wavelength λ. If the proton is moving at non-relativistic speed, find the ratio of the de Broglie wavelength of the proton to the wavelength of the photon.(Shift - I Memory Based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
A proton of mass '\({m}_{p}\)' has same energy as that of a photon of wavelength '\(\lambda\)'. If the proton is moving at non-relativistic speed, then ratio of its de Broglie wavelength to the wavelength of photon is.
[JEE Main 2025, 28 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (Cs) and lithium (Li) metals are 1.9 eV and 2.5 eV , respectively. If we incident a light of wavelength 550 nm on these two metal surfaces, then photo-electric effect is possible for the case of
Options are free to see. Unlock the correct answer and full explanation with Pass.
In photoelectric experiment energy of \(2.48\mathrm{eV}\) irradiates a photo sensitive material. The stopping potential was measured to be \(0.5\mathrm{V}\). Work function of the photo sensitive material is :
Options are free to see. Unlock the correct answer and full explanation with Pass.
In an experiment with photoelectric effect, the stopping potential,
[JEE Main 2025, 29 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The work functions of cesium (\(\text{Cs}\)) and lithium (\(\text{Li}\)) metals are \(1.9\text{ }\text{eV}\) and \(2.5\text{ }\text{eV}\), respectively. If light of wavelength 550 nm is incident on these two metal surfaces, for which metal(s) will the photoelectric effect occur? (Planck’s constant \(h=6.63\times 1{0}^{−34}\text{ }\text{Js}\), Speed of light \(c=3\times 1{0}^{8}\text{ }\text{m/s}\).)
[JEE Main 2025, 22 Jan (Shift 1)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
Let \({\lambda }_{e},{\lambda }_{p}\) and \({\lambda }_{d}\) be the wavelengths associated with an electron, a proton and a deuteron, all moving with the same speed. Then the correct relation between them is
Options are free to see. Unlock the correct answer and full explanation with Pass.
A light source of wavelength \(\lambda\) illuminates a metal surface and electrons are ejected with maximum kinetic energy of 2 eV . If the same surface is illuminated by a light source of wavelength \(\frac{\lambda }{2}\), then the maximum kinetic energy of ejected electrons will be (The work function of metal is 1 eV )
[JEE Main 2025, 22 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The energy E and momentum p of a moving body of mass m are related by some equation. Given that c represents the speed of light, identify the correct equation
[JEE Main 2025, 24 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
The relation between energy E and momentum p of a photon is
(Shift - II Memory based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
In photoelectric effect, the stopping potential \(\left({V}_{0}\right)\)v/s frequency (\(\nu\)) curve is plotted.
( h is the Planck's constant and \({ϕ}_{0}\) is work function of metal)
(A) \({V}_{0}\) v/s \(\nu\) is linear.
(B) The slope of \({V}_{0}\) v/s \(\nu\) curve \(=\frac{{ϕ}_{0}}{h}\)
(C) h constant is related to the slope of \({V}_{0}\) v/s \(\nu\) line.
(D) The value of electric charge of electron is not required to determine h using the \({V}_{0}\) v/s \(\nu\) curve.
(E) The work function can be estimated without knowing the value of h.
Choose the correct answer from the options given below :
[JEE Main 2025, 24 Jan (Shift 2)]
Options are free to see. Unlock the correct answer and full explanation with Pass.
Which of the following phenomena cannot be explained using the wave theory of light?
(Shift - II Memory Based)
Options are free to see. Unlock the correct answer and full explanation with Pass.
A graph is plotted between the stopping potential (on y-axis) and the frequency of incident radiation (on \(x\)-axis) for a metal. The product of the slope of the straight line obtained and the magnitude of charge on an electron is equal to :
Options are free to see. Unlock the correct answer and full explanation with Pass.
A beam of light travels from air into a medium. Its speed and wavelength in the medium are \(1.5 \times 10^8 ms ^{-1}\) and \(230 nm\) respectively. The wavelength of light in air will be
Options are free to see. Unlock the correct answer and full explanation with Pass.
Assertion (A) and Reason (R) type questions. Two statements are given one labelled Assertion (A) and the other labelled Reason
(R). Select the correct answer from the codes (A), (B), (C) and (D) as given below.
Assertion (A) : Photoelectric current increases with an increase in intensity of incident radiation, for a given frequency of incident radiation and the accelerating potential.
Reason (R) : Increase in the intensity of incident radiation results in an increase in the number of photoelectrons emitted per second and hence an increase in the photocurrent.
Options are free to see. Unlock the correct answer and full explanation with Pass.
Assertion (A): Photoelectric effect demonstrates the particle nature of light.
Reason (R): Photoelectric current is proportional to intensity of incident radiation for frequencies more than the threshold frequency.
Options are free to see. Unlock the correct answer and full explanation with Pass.
Assertion (A): The energy (E) and momentum (p) of a photon are related as \(p =\frac{ h }{ E }\).
Reason \((R)\) : Photons behave as a wave.
Options are free to see. Unlock the correct answer and full explanation with Pass.
Assertion (A) : In photoelectric effect, the kinetic energy of the emitted photoelectrons increases with increase in the intensity of the incident light.
Reason (R) : Photoelectric current depends on the wavelength of the incident light.
Options are free to see. Unlock the correct answer and full explanation with Pass.
Light of frequency \(6.4 \times 10^{14} Hz\) is incident on a metal of work function \(2 \cdot 14 eV\). The maximum kinetic energy of the emitted electrons is about :
Options are free to see. Unlock the correct answer and full explanation with Pass.
Which one of the following metals does not exhibit emission of electrons from its surface when irradiated by visible light?
Options are free to see. Unlock the correct answer and full explanation with Pass.
The energy of a photon of wavelength \(\lambda\) is
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two statements are given - one labelled Assertion (A) and the other labelled Reason \((R)\). Select the correct answer from the codes (A), (B), (C) and (D) as given below.
Assertion (A) : Photoelectric effect demonstrates the particle nature of light.
Reason (R) : Photoelectric current is proportional to frequency of incident radiation.
Options are free to see. Unlock the correct answer and full explanation with Pass.
For questions , two statements are given - one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
Assertion (A) : Electrons are ejected from the surface of zinc when it is irradiated by yellow light.
Reason (R) : Energy associated with a photon of yellow light is more than the work function of zinc.
Options are free to see. Unlock the correct answer and full explanation with Pass.
Two statements are given - one labelled Assertion (A) and the other labelled Reason \((R)\). Select the correct answer from the codes (A), (B), (C) and (D) as given below.
Assertion (A) : In photoelectric effect, the kinetic energy of the emitted photoelectrons increases with increase in the intensity of the incident light.
Reason (R): Photoelectric current depends on the wavelength of the incident light.
Options are free to see. Unlock the correct answer and full explanation with Pass.
An electron and an alpha particle are accelerated by the same potential difference. Let \({\lambda }_{e}\) and \({\lambda }_{\alpha }\) denote the de Broglie wavelengths of the electron and the alpha particle respectively, then:
Options are free to see. Unlock the correct answer and full explanation with Pass.
The wave character of electron was experimentally verified by:
Options are free to see. Unlock the correct answer and full explanation with Pass.
Practice more Board Physics PYQs
Browse every Physics chapter, or explore the full Board question bank.
All Physics chapters →