List of top Chemistry Questions on Photoelectric Effect

Which of the following statements are correct, if the threshold frequency of caesium is $ 5.16 \times 10^{14} \, \text{Hz} $?

The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency $ 'A' \times 10^{12} \, \text{hertz} $ and that has a radiant intensity in that direction of $ \frac{1}{'B'} \, \text{watt per steradian} $. 'A' and 'B' are respectively:

When a metal surface is illuminated by light of wavelengths 400nm and 250nm, the maximum velocities of the photoelectrons ejected are v and 2v respectively. The work function of the metal is

Find the number of photons emitted per second by a 25 watt source of monochromatic light of wavelength 6600AA. What is the photoelectric current assuming 3% efficiency for photoelectric effect?

When 0.50AA X-rays strike a material, photoelectrons from the K shell are observed to move in a circle of radius 23mm in a magnetic field of 2×10⁻2T acting perpendicular to the direction of emission. What is the binding energy of K-shell electrons?

The beam of light has three wavelengths 4144AA, 4972AA, 6216AA with a total intensity of 3.6×10⁻3W/m² equally distributed among the three wavelengths. The beam falls normally on a clean metallic surface of work function 2.3eV. Assuming no loss by reflection and that each photon ejects one photoelectron, calculate the number of photoelectrons liberated in 2s.

When a metal surface is illuminated by light of wavelength 400 nm and 250 nm, the maximum velocities of the photoelectrons ejected are v and 2v respectively. The work function of the metal is (h = Planck’s constant, c = velocity of light in air)

Find the number of photons emitted per second by a 25W source of monochromatic light of wavelength 6600AA. What is the photoelectric current assuming 3% efficiency for photoelectric effect?

When $0.5\,\text{\AA}$ X-rays strike a material, the photoelectrons from the K-shell are observed to move in a circular path of radius $23\,\text{mm}$ in a magnetic field of $2 \times 10^{-2}\,\text{T}$, perpendicular to the direction of emission of photoelectrons. What is the binding energy of K-shell electrons?

The beam of light has wavelengths $4144\,\text{\AA}$, $4972\,\text{\AA}$, and $6216\,\text{\AA}$ with a total intensity of $3.6 \times 10^{-3}\,\text{W m}^{-2}$ equally distributed among the three wavelengths. The beam falls normally on an area of $1\,\text{cm}^2$ of a clean metallic surface of work function $2.3\,\text{eV}$. Assume that there is no loss of light by reflection and that each energetically capable photon ejects one electron. Calculate the number of photoelectrons liberated in $2\,\text{s}$.

Graph between stopping potential of most energetic emitted photoelectrons ($V_s$) and frequency ($\nu$) of incident radiation on metal is given. Value of slope AB/BC in graph is [where $h$ = Planck’s constant, $e$ = electronic charge]:

The threshold wavelength of tungsten is $2300\,\text{\AA}$. If ultraviolet light of wavelength $1800\,\text{\AA}$ is incident on it, then the maximum kinetic energy of photoelectrons would be about:

In an experiment on photoelectric effect photons of wavelength 300 nm eject electrons from a metal of work function 2.25 eV. A photon of energy equal to that of the most energetic electron corresponds to the following transition in the hydrogen atom:

A light having wavelength 300 nm falls on a metal surface. The work function of metal is 2.54 eV, what is stopping potential?

The photoelectric threshold of a metal is 2000. The energy of electrons ejected from the surface by ultraviolet light of wavelength 1500 is