Dual nature of radiation and matter practice · Medium

A photoelectric cell is illuminated by a point source of light 1 m away. When the source is shifted to 2 m then

A photon has same wavelength as the de-Broglie wavelength of electrons. Given $C=$ Speed of light $\mathrm{V}=$ Speed of electron

$E_e=$ Kinetic energy of electrons

$E_{P h}=$ Kinetic energy of photon

$P_e=$ Momentum of electron

$P_{Ph}=$ Momentum of photon

Which of the following is correct?

Positive rays consists of

Photons absorbed in matter are converted to heat. A source emitting $n$ photon/s of frequency $v$ is used for converting of ice at $0^{\circ} {C}$ to water at $0^{\circ} {C}$. Then, which amongst the following is incorrect regarding the time, $T$ taken for the conversion?

A monochromatic source of light operating at $200 \mathrm{~W}$ emits $4 \times 10^{20}$ photons per second. Find the wavelength of the light.

Proton $(P)$ and electron $(e)$ will have same de-Broglie wavelength when the ratio of their momentum is (assume, ${m}_{{p}}=1849 \, {M}_{{e}}$ ):

A photon in motion has a mass equal to

The de-Broglie wavelength associated with electron in $n^{\text {th }}$ Bohr orbit is (where $r$ is radius of $n^{\text {th }}$ Bohr orbit)

If alpha, beta and gamma rays carry same momentum, which has the longest wavelength?

The work function of aluminium is 4.2 eV. If two photons each of energy 3.5 eV strike an electron of aluminium, then emission of electron will

Albert Einstein was awarded Nobel Prize and his work on

Kinetic energy of emitted cathode rays is dependent on

Light of intensity $I_1$ is incident on a photosensitive metal plate which gives rise to a saturation current $\left(I_S\right)$. Now, if the intensity of the radiation is increased keeping the frequency constant, then the saturation current will be;

The de-Broglie wavelength associated with the particle of mass $m$ moving with velocity $v$ is

The velocity of photon is proportional to (where $v$ is frequency)

Assertion: A photocell is a technological application of the photoelectric effect.
Reason: Photocell is a device whose electric properties are affected by electricity.

If an electron and proton are propagating in the form of waves having the same wavelength, it implies that they have the same

Photon of frequency $v$ has a momentum associated with it. If $c$ is the velocity of light, the momentum is

If ${n_R}$ and ${n_V}$ denote the number of photons emitted by a red bulb and violet bulb of equal power in a given time, then

The de-Broglie wavelength $\lambda$

Assertion: if the frequency of the incident light on a metal surface is doubled, the kinetic energy of emitted electrons is more than doubled.

Reason: The metal will provide additional energy to the emitted photoelectron for light of higher frequency than that for lower frequency.

Which of the following relations is a correct Einstein's photoelectric equation? [All symbols have their usual meaning]

Positive rays were discovered by

Choose the correct option from the following options given below:

Calculate the momentum and de Broglie wavelength of the electrons accelerated through a potential difference of $56 \mathrm{~V}$.

Dual nature of radiation is shown by

Assertion: When photons of frequency $4.3 \times 10^{15} \mathrm{~Hz}$ is incident on the surface of threshold frequency $5 \times 10^{15} \mathrm{~Hz}$ then no photoelectron emitted from the surface.

Reason: Number of electrons ejected depends on intensity.

Assertion: The threshold frequency of photoelectric effect supports the particle nature of light.

Reason: If frequency of incident light is less than the threshold frequency, electrons are not emitted from metal surface.

What determines the hardness of the $X$-rays obtained from the coolidge tube

Calculate momentum of a photon associated with a radiation of frequency $5 \times 10^{13} \mathrm{~Hz}$ Given $h=6.6 \times 10^{34} \mathrm{~Js}$ and $c=3 \times 10^8 \mathrm{~ms}^{-1}$.