Dual nature of radiation and matter practice · Mixed difficulty

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

Assertion: Through light of a single frequency (mono-chromatic) is incident on a metal, the energies of emitted photoelectrons are different.

Reason: the energy of electrons emitted from inside the metal surface is lost in collision with the other atoms in the metal.

When light falls on a metal surface, the maximum kinetic energy of the emitted photo-electrons depends upon

Assertion: The wave nature of electrons was first experimentally verified by Davisson and Germer Experiment.

Reason: From the electron diffraction measurements, the wavelength of matter waves was found to be $0.165 \mathrm{~nm}$.

A particle which has zero rest mass and non-zero energy and momentum, must travel with a speed

For the Bohr's first orbit of circumference $2\pi r,$ the de-Broglie wavelength of revolving electron will be.

A photon is emitted by a hydrogen atom when it comes from excited state $\mathrm{n}=5$ to the ground state. The recoil speed is almost

Which of the following is not possible value of radius of stable orbit of hydrogen atom. Where $\lambda$ is de Broglie wavelength of the electron.

Statement 1: Mass of moving photon varies inversely as the wavelength.

Statement 2: Energy of the particle $=$ Mass $\times(\text { Speed of light })^2$

In photoelectric effect, the KE of electrons emitted from the metal surface depends upon

Photoelectric effect supports quantum nature of light because
1. There is minimum frequency of light below which no photoelectrons are emitted.
2. Electric charge of photoelectrons is quantized.
3. Maximum kinetic energy of photoelectrons depends only on the frequency of light and not on its intensity.
4. Even when metal surface is faintly illuminated the photoelectrons leave the surface immediately.

An electron with mass 'm' with an initial velocity $(\text{t}=0)$ $\vec{\mathrm{v}}=\mathrm{v}_0 \hat{\mathrm{i}} \left(\mathrm{v}_0>0\right)$ enters a magnetic field $\vec{\mathrm{B}}=\mathrm{B}_0 \hat{\mathrm{j}}.$ If the initial de-Broglie wavelength at $\mathrm{t}=0$ is $\lambda_0$ then its value after time 't' would be:

Ultraviolet radiation of 6.2 eV falls on an aluminium surface (work function 4.2 eV). The kinetic energy of the faster electron emitted is approximately

The number of photo-electrons emitted per second from a metal surface increases when

In cathode ray oscillograph, the focusing of beam on the screen is achieved by

When ultraviolet rays are incident on metal plate, then photoelectric effect does not occur. It occurs by the incidence of

If a photoemissive surface has a threshold frequency of $4.6 \times 10^{14} \mathrm{~Hz}$, calculate the energy of the photons in $\mathrm{eV}$. Given $h=6.6 \times 10^{-34} \mathrm{~Js}$.

Vidicon works on the principle of

The stopping potential for electrons emitted from a photosensitive surface illuminated by light of wavelength $491nm\,$ is $0.710V$. When the incident wavelength is changed to a new value, the stopping potential is $1.43V.$ The new wavelength is

Which is the correct ascending order of wavelengths?