List of top Physics Questions on Photoelectric Effect asked in MHT CET

Light of incident frequency three times the threshold frequency is incident on a photo sensitive material. If the incident frequency is made \(\left(\frac{1}{3}\right)^{rd}\) and intensity is doubled then photoelectric current will
Radiation of wavelength \(\lambda\), is incident on a photocell. The fastest emitted electron has speed \(v\). If the wavelength is changed to \(\frac{3\lambda }{4}\), the speed of the fastest electron will be
When a metallic surface is illuminated with radiation of wavelength \(\lambda\), the stopping potential is \(V\). If the surface is now illuminated with a radiation of wavelength \(4\lambda\), the stopping potential \(\left(\frac{V}{8}\right)\). The threshold wavelength for the surface is
In an experiment on photoelectric effect, the stopping potential \(V_{0}\) is plotted against the frequency \(\nu\) of the incident light. Considering \(e\) as the electronic charge, the work function of the photoelectric surface is given by
When a certain metal surface is illuminated with a light of wavelength \(\lambda\), the stopping potential is \(V\). When the same surface is illuminated by light of wavelength \(2\lambda\), the stopping potential is \(\left(\frac{V}{3}\right)\). The threshold wavelength for the surface is
Light of wavelength \(\lambda\) strikes a photoelectric surface and electrons are ejected with an energy \(E\). If \(E\) is to be increased to exactly twice its original value, the wavelength changes to \(\lambda _{1}\) where
Energy of the incident photon on the metal surface is \(3W\) and then \(5W\), where \(W\) is the work function of that metal. The ratio of velocities of emitted photoelectrons is
When photons of energy \(h\nu\) fall on a metal plate of work function \(W_{0}\), photoelectrons of maximum kinetic energy K are ejected. If the frequency of radiation is doubled, the maximum kinetic energy of ejected photoelectrons will be
A point source of light is used in a photoelectric effect. If the source is moved farther from the emitting metal, then the stopping potential
The frequency of the incident light falling on a photosensitive metal plate is doubled, the kinetic energy of the emitted photoelectrons is
A photon of energy \(10\) units ejects a photo-electron from a metal surface whose work function is \(\Phi _{0}\). If an electron(e) having maximum kinetic energy enters into a uniform magnetic field of induction(B) in a direction perpendicular to the field and describes a circular path of radius R, then radius R is {\(m=\)mass of electron}
A light of wavelength \(\lambda\) \((\lambda \lt \lambda _{0})\) falls on a metal surface. The momentum of the fastest moving electron is \(p\). In order to have the momentum of an electron equal to \(2p\), the required wavelength \(\lambda '\) of incident light must be
A student plots two different graphs using the same photoelectric experiment data.
1. Maximum kinetic energy (\(K_{max}\)) against frequency (\(\nu\))
2. Stopping potential (\(V_{o}\)) against frequency (\(\nu\))
Let the slope of graph 1 be \(S_{1}\) and the slope of graph 2 be \(S_{2}\).
What is the relationship between the slopes?
(h = Planck's constant, e = charge on electron)
Statement I- When the wavelength of incident radiation in a photoelectric experiment is decreased, then the stopping potential will decrease.
Statement II- In photoelectric effect, if the intensity of light is doubled, then the maximum kinetic energy of photoelectrons will become double.
When a light beam of frequency \(\upsilon\) is incident on a metal surface, photoelectrons are emitted. If these electrons describe a circle of radius r in a magnetic field of strength B, then the work function of the metal is
\((h=\) Planck's constant, \(m_{e}=\) mass of electron, \(e=\) charge on electron\()\)
In a photoelectric cell, for the incident radiation of wavelength \(\lambda\), the fastest electron has speed 'v'. If the wavelength of incident radiation is changed to \(\frac{\lambda }{3}\), the speed of the fastest emitted electron is
Light of frequency \(4\nu _{0}\) is incident on the metal of threshold frequency \(\nu _{0}\). The maximum kinetic energy of the emitted photoelectron is ( h = Planck's constant)
In the case of the photo-electric effect, which of the following sentences is NOT TRUE?
a. The photo-electrons are emitted only when the frequency of incident radiation is greater than the threshold frequency.
b. There is no time lag between incidence of light and emission of electrons.
c. The rate of photo-electric emission is independent of the intensity of incident radiation.
d. The maximum kinetic energy of emitted photo-electrons depends on the frequency of incident radiation.
If the photoelectric work function of a metal is '\(\phi\)' and the frequency of incident light is '\(\nu\)', there is no emission of photoelectrons if
A photon of energy 8 eV is incident on a metal surface of work function 3.75 eV. The stopping potential of the metal is
When light of wavelength '\(\lambda\)' is incident on a photosensitive surface, the stopping potential is '\(V\)'. When light of wavelength '\(2\lambda\)' is incident on the same surface, the stopping potential is \(V/3\). Threshold wavelength for the surface is
At the stopping potential, the photoelectrons have
Two identical photocathodes receive light of frequencies \(n_1\) and \(n_2\). If the velocities of the emitted photoelectrons of mass m are \(V_1\) and \(V_2\) respectively, then (\(h\) = Planck's constant)
When light of wavelength '\(λ\)' is incident on a photosensitive surface, the stopping potential is 'V'. When a light of wavelength \(1.5λ\) is incident on the same surface, the stopping potential is '\(\frac{V}{4}\)'. Threshold wavelength for the surface is
A photoelectric surface is illuminated successively by monochromatic light of wavelength \(λ\) and \((λ/3)\). If the maximum kinetic energy of the emitted photo electrons in the second case is \(4\) times that in the first case, the work function of the surface of the material is (\(h\) = Planck's constant, \(c\) = speed of light)