List of top Physics Questions on Photoelectric Effect asked in CBSE CLASS XII

While studying photoelectric emission from a given surface, the wavelength of the incident radiation is changed from \(600\,\text{nm}\) to \(400\,\text{nm}\), keeping the intensity of radiation the same. Then :

Radiation of wavelength \(331\ \text{nm}\) irradiates the following metals :

Which of the following statements is correct ?

Assertion (A) : Photoelectric current depends upon the intensity of the incident radiation.
Reason (R) : Stopping potential is independent of the intensity of the incident radiation.

Radiation of wavelength 200 nm is incident on a photosensitive surface of work function 4·2 eV. The kinetic energy of fastest photoelectrons emitted from this surface will be close to :

A researcher performs an experiment on photoelectric effect using two metals A and B with unknown work functions. She illuminates the surfaces of A and B with monochromatic radiation of various frequencies and records the corresponding stopping potentials \((V_s)\). The graph shows the variation of stopping potential \((V_s)\) with the frequency of incident radiation \((\nu)\) for metals A and B.

Answer the following questions:

A researcher performs an experiment on photoelectric effect using two metals A and B with unknown work functions. She illuminates the surfaces of A and B with monochromatic radiation of various frequencies and records the corresponding stopping potentials \((V_s)\). The graph shows the variation of stopping potential \((V_s)\) with the frequency of incident radiation \((\nu)\) for metals A and B.

Answer the following questions:

Assertion (A): On increasing the intensity of incident light of frequency \( v(> v_0) \) on a photosensitive surface, the photocurrent increases. Reason (R): The stopping potential for a photosensitive surface increases with increase of frequency \( v(> v_0) \) of incident light.

The maximum kinetic energy of photoelectrons depends on

In a photoelectric experiment, the emitter plate is irradiated with radiation of \(200\ \text{nm}\). The photocurrent becomes zero when the collector plate potential is \(-0.80\ \text{V}\). Calculate the work function (in eV) of the emitter.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate: Energy of a photon in the incident light.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate the maximum kinetic energy of the emitted electrons.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate the stopping potential.

Assertion (A) : Photoelectric effect is a spontaneous phenomenon. Reason (R) : According to the wave picture of radiation, an electron would take hours/days to absorb sufficient energy to overcome the work function and come out from a metal surface.

Assertion (A): On increasing the intensity of incident light of frequency \( v(> v_0) \) on a photosensitive surface, the photocurrent increases. Reason (R): The stopping potential for a photosensitive surface increases with increase of frequency \( v(> v_0) \) of incident light.

The maximum kinetic energy of photoelectrons depends on

In a photoelectric experiment, the emitter plate is irradiated with radiation of \(200\ \text{nm}\). The photocurrent becomes zero when the collector plate potential is \(-0.80\ \text{V}\). Calculate the work function (in eV) of the emitter.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate the stopping potential.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate: Energy of a photon in the incident light.

Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate the maximum kinetic energy of the emitted electrons.

Assertion (A) : Photoelectric effect is a spontaneous phenomenon. Reason (R) : According to the wave picture of radiation, an electron would take hours/days to absorb sufficient energy to overcome the work function and come out from a metal surface.

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.