# Dual Nature of Radiation · Physics · COMEDK

Start Practice## MCQ (Single Correct Answer)

COMEDK 2024 Evening Shift

A photon emitted during the de-excitation of electron from a state $$\mathrm{n}$$ to the second excited state in a hydrogen atom, irradiates a metalli...

COMEDK 2024 Evening Shift

A particle of mass $$2 \mathrm{mg}$$ has the same wavelength as a neutron moving with a velocity of $$3 \times 10^5 \mathrm{~ms}^{-1}$$. The velocity ...

COMEDK 2024 Morning Shift

The threshold frequency for a metal surface is '$$n_0$$'. A photo electric current '$$I$$' is produced when it is exposed to a light of frequency $$\l...

COMEDK 2024 Morning Shift

The mass of a particle $$\mathrm{A}$$ is double that of the particle $$\mathrm{B}$$ and the kinetic energy of $$\mathrm{B}$$ is $$\frac{1}{8}$$th that...

COMEDK 2024 Morning Shift

The difference in energy levels of an electron at two excited levels is $$13.75 \mathrm{~eV}$$. If it makes a transition from the higher energy level ...

COMEDK 2023 Morning Shift

When a certain metal surface is illuminated with light of frequency $$\nu$$, the stopping potential for photoelectric current is $$V_0$$. When the sam...

COMEDK 2023 Morning Shift

Let $$K_1$$ be the maximum kinetic energy of photoelectrons emitted by light of wavelength $$\lambda_1$$ and $$K_2$$ corresponding to wavelength $$\la...

COMEDK 2023 Evening Shift

In the photoelectric experiment, the frequency of the incident radiation is doubled. What will be its effect on the photoelectric current?

COMEDK 2022

Ultraviolet light of wavelength 99 mm falls on a metal plate of work function 1.0 eV. If the mass of the electron is 9.1 $$\times$$ 10$$^{-31}$$ kg, t...

COMEDK 2022

If K$$_1$$ and K$$_2$$ are maximum kinetic energies of photoelectrons emitted when lights of wavelengths $$\lambda_1$$ and $$\lambda_2$$, respectively...

COMEDK 2021

The velocity of the proton is one-fourth the velocity of the electron. What is the ratio of the de-Broglie wavelength of an electron to that of a prot...

COMEDK 2021

From the figure describing photoelectric effect, we may infer correctly that
...

COMEDK 2020

Light of frequency 1015 Hz falls on a metal surface of work function 2.5 eV. The stopping potential of photoelectrons (in V) is

COMEDK 2020

A proton accelerated through a potential V has de-Broglie wavelength $$\lambda$$. Then, the de-Broglie wavelength of an $$\alpha$$-particle, when acce...