Dual nature of radiation and matter practice · Mixed difficulty

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

A beam of $10.6 \mathrm{~eV}$ photons of intensity $2.0 \mathrm{~W} / \mathrm{m}^2$ falls on a platinum surface of area $1.0 \times 10^{-4} \mathrm{~m}^2$ and work function $5.6 \mathrm{~eV}$. If $0.53 \%$ of the incident photons eject photo electrons, then find the number of photoelectrons emitter per second and maximum energy of ejected electrons (in $\mathrm{eV}$) are

Relation between the stopping potential ${V_0}$ of a metal and the maximum velocity v of the photoelectron is

Wave equation of light used in PEE at a given point is given by $\mathrm{E}=\mathrm{E}_0[\sin 5 \omega \mathrm{t}+\cos 15 \omega \mathrm{t}]$ here $\mathrm{t}$ is instant, If work function of electron emitter is $\phi$ then value of stopping potential will be:-

Assertion: Two sources of equal intensity always emit equal number of photons in any time interval.

Reason: Two sources of equal intensity may emit equal number of photons in any time interval.

In photoelectric experiment energy of $2.48 \mathrm{~eV}$ irradiates a photo sensitive material. The stopping potential was measured to be $0.5 \mathrm{~V}$. Work function of the photo sensitive material is :

Find the typical de Broglie wavelength associated with a $He$ atom in helium gas at room temperature $\left(27^{\circ} \mathrm{C}\right)$ and $1 \mathrm{~atm}$ pressure?

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 threshold frequency for a certain photosensitive metal is ${\upsilon _0}$ When it is illuminated by light of frequency $\upsilon = 2{\upsilon _0}$,the maximum velocity of photoelectrons is ${v_0}$. What will be the maximum velocity of the photoelectrons when the same metal is illuminated by light of frequency $\upsilon = 5{\upsilon _0}$ ?

Hydrogen gas in the atomic state is excited to an energy level such that the electrostatic potential energy of hydrogen atom becomes -1.7 eV. Now a photoelectric plate having work function 2.3 eV is exposed to the emission spectra of this gas. Assuming all the transitions to be possible, find the minimum de-Broglie wavelength of the ejected photoelectrons in $\mathop {\text{A}}\limits^ \circ$ to the nearest integer.

An oil drop with charge $q$ is held stationary between two plates with an external potential difference of 400 V. If the size of the drop is doubled without any change of charge, the potential difference required to keep the drop stationary will be

de-Broglie wavelength of a proton and an electron is same. The ratio of kinetic energy of electron to that of proton is

Assertion (A): Work function of aluminium is 4.2 eV. Emission of electron will not be possible if two photons each of energy 2.5 eV strike an electron of a aluminium.
Reason (R): For photoelectron emission the energy of each photon should be greater than the work function of metal.

A photon, an electron and a uranium nucleus all have the same wavelength. The one with the most energy

For a body moving with relativistic speed, if the velocity is doubled, then

An electron is accelerated by a potential difference of V volt to acquire kinetic energy equal to maximum kinetic energy of ejected photoelectron from a metal of work function 3.2 eV, using a light of wavelength $2000\,\mathop \mathrm{A}\limits^ \circ \,$ Value of V is

A broken ligament is being ‘welded’ back in place using 20 ms pulses from a 0.5 W laser operating at a wavelength of 632 nm. The number of photons in 5 pulses of laser are

The ratio transmitter operates on a wavelength of 1500 m at a power of 400 kW. The energy of radio photon (in joule) is

Kinetic mass of photon is

The mean free path of the electrons in a discharge tube is 20 cm. The length of the tube is 15 cm only. Then length of Crooke’s dark space is

The special theory of relativity is based on the frame of reference which has constant?

Photo cell is a device to

The de-Broglie wavelength $\lambda$ associated with an electron having kinetic energy $E$ is given by the expression

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

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

A proton is accelerated through a potential difference of $400 \mathrm{~V}$ to have same de-Broglie wavelength what potential difference must be applied across doubly ionised ${ }_8 {O}^{16}$ atom:

The magnitude of saturation photoelectric current depends upon

The minimum energy required to eject an electron, from the metal surface is called

In a photocell bichromatic light of wavelength $2475\mathop A\limits^ \circ$ and $6000\;\mathop A\limits^ \circ$ are incident on cathode whose work function is $4.8\;eV.$ If a uniform magnetic field of $3 \times {10^{ - 5}}tesla$ exists parallel to the plate, the radius of the path described by the photoelectron will be (mass of electron $= 9 \times {10^{ - 31}}kg$)

G. P. Thomson experimentally confirmed the existence of matter waves by the phenomenon