Dual nature of radiation and matter practice · Medium

Assertion: Photoelectric effect supports the quantum nature of light.

Reason: Photoelectric emission is instantaneous.

When a metallic surface is illuminated with monochromatic light of wavelength $\lambda$, stopping potential for photoelectric current is $3 \mathrm{~V}_0$. When the same metallic surface is illuminated with a light of wavelength $2 \lambda$, the stopping potential is $V_0$. The threshold wavelength for the surface is-

An electron is accelerated through a potential difference of $V$ volt. The speed of electrons will be

Two sources of light emit with a power of $200 {~W}$. The ratio of number of photons of visible light emitted by each source having wavelengths 300 ${nm}$ and $500 {~nm}$ respectively, will be :

Which of the following statement about photon is incorrect?

Ultraviolet light of wavelength $280 \mathrm{~nm}$ is used in an experiment on photoelectric effect with lithium $(\varphi=2.5 \mathrm{~eV})$ cathode. Find

(a) the maximum kinetic energy of the photoelectrons and

(b) the stopping potential.

Which of one is correct

If an electron and a proton have the same de-Broglie wavelength, then the kinetic energy of the electron is

The wavelength of light in the visible region is about $390 \mathrm{~nm}$ for violet colour. What are the energies of photons in $(\mathrm{eV})$ at the violet end. [Take $h=6.63 \times 10^{-34} \mathrm{~Js}$ and $1 \mathrm{~eV}=1.6 \times 10^{-19} \mathrm{J}]$.

The ratio of the de-Broglie wavelength of an $\alpha$-particle and a proton of same kinetic energy is

In which of the following cases the heavier of the two particle has a same de Broglie wavelength? The two particles :-

When ultraviolet radiation is incident on a surface, no photoelectrons are emitted. If a second beam causes photoelectrons to be ejected, it may consist of

The ratio of the energy of a photon with $\lambda = 150$ nm to that with $\lambda = 300$ nm is

Photoelectric effect can be explained by

The energy of an electron in the ${n^{th}}\,$ Bohr’s orbit is proportional to

If the uncertainty in the position of an electron is ${10^{ - 10}}$m, then the value of uncertainty in its momentum (in kg-$\mathrm{m}{\mathrm{s}^{ - 1}}$) will be

A ultra violet photon and an electron have the same de Broglie wavelengths, then the energy of the photon is -

If ${\mathrm{g}_E}$ and ${\mathrm{g}_M}$ are the acceleration due to gravity on the surfaces of the earth and the moon respectively and it Millikan’s oil drop experiment could be performed on the two surfaces, one will find the ratio $\frac{{\mathrm{electronic\;charge\;on\;the\;moon\;}}}{{\mathrm{electronic\;charge\;on\;the\;earth\;}}}$ to be

A small piece of cesium metal $(\varphi=1.9 \mathrm{~eV})$ is kept at a distance of $20 \mathrm{~cm}$ from a large metal plate having a charge density of $1.0 \times 10^{-9} \mathrm{C} \mathrm{~m}^{-2}$ on the surface facing the cesium piece. A monochromatic light of wavelength $400 \mathrm{~nm}$ is incident on the cesium piece. Find the minimum and the maximum kinetic energy of the photoelectrons reaching the large metal plate. Neglect any change in electric field due to the small piece of cesium present.

An electron and a proton have the same de-Broglie wavelength. Then the kinetic energy of the electron is

Assertion: The kinetic energy of photoelectrons depends on the frequency of incident radiation.

Reason: The kinetic energy of photoelectrons is determined by the difference between the energy of the incident photon and the work function of the metal.

If $\lambda_{\mathrm{p}}$ and $\lambda_\alpha$ be the wavelengths of protons and $\alpha$-particles of equal kinetic energies, then

What is the de Broglie wavelength of
(a) a ball of mass $0.060 \mathrm{~kg}$ moving at a speed of $1.0 \mathrm{~m} / \mathrm{s}$, and
(b) a dust particle of mass $1.0 \times 10^{-9} \mathrm{~kg}$ drifting with a speed of $2.2 \mathrm{~m} / \mathrm{s}$?

Electric field and magnetic field in Thomson mass spectrograph are applied

A photon and electron have same de-Broglie wavelength. Give that $v$ is the speed of electron and $c$ is the velocity of light. ${E_e},\;{E_p}$ are the kinetic energy of electron and photon respectively. ${p_e},\;{p_h}$ are the momentum of electron and photon respectively. Then which of the following relation is correct?

The threshold frequency for photo electric effect on sodium corresponds to a wave length of $6000\,\,{A^ \circ }.$ Its work function is [Joule]

Which is not true with respect to the cathode rays

A photo cell is receiving light from a source placed at a distance of $1\;m.$ If the same source is to be placed at a distance of $2\;m,$ then the ejected electron

A photon collides with a stationary hydrogen atom in ground state inelastically. Energy of the colliding photon is 10.2 eV. After a time interval of the order of micro second another photon collides with same hydrogen atom inelastically with an energy of 15 eV. What will be observed by the detector?

A Rn photodiode is fabricated from a semiconductor with a band gap of 2.5 eV. It can detect a signal of wavelength