Advertisements
Advertisements
प्रश्न
Find the wave number of a photon having energy of 2.072 eV
Given : Charge on electron = 1.6 x 10-19 C,
Velocity of light in air = 3 x 108 m/s,
Planck’s constant = 6.63 x 10-34 J-s.
Advertisements
उत्तर
E = hv
`:.v=E/h`
`v=C/lambda`
∴ Wave number
`1/lambda=v/c`
`=E/(hc)`
`=(2.072xx1.6xx10^(-19))/(6.63xx10^(-34)xx3xx10^8`
`=1/lambda=1.667xx10^6m^(-1)`
APPEARS IN
संबंधित प्रश्न
The momentum of a photon of de Broglie wavelength 5000Å is _______.
[Planck’s constant = 6.63 x10-34 J.s.]
When radiations of wavelength λ1 and λ2 are incident on certain photosensitive, such that E1 > E2 . Then Planck's constant 'h' is ......................... .
(C = Velocity of light).
The photoelectric threshold wavelength of a metal is 230 nm. Determine the maximum kinetic energy in joule and in eV of the ejects electron for the metal surface when it is exposed to a radiation of wavelength 180 nm.
[Planck’s constant : h = 6.63 * 10-34 Js, Velocity of light : C = 3 * 108 m/s.]
State two important properties of photon which are used to write Einstein’s photoelectric equation.
Write Einstein's photoelectric equation and mention which important features in photoelectric effect can be explained with the help of this equation.
The maximum kinetic energy of the photoelectrons gets doubled when the wavelength of light incident on the surface changes from λ1 to λ2. Derive the expressions for the threshold wavelength λ0 and work function for the metal surface.
Write its S.I. unit of (intensity of radiation)
Write the basic features of photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based.
According to Einstein’s model minimum energy needed for the electron to escape from a metal surface having work function ϕ0, the electron is emitted with maximum kinetic energy, Kmax = ______.
According to Einstein’s model, the threshold frequency for a metal having work function ϕ0 is given by _________.
According to the Einstein’s model, stopping potential Vo for a metal having work function ϕ0 is given by ______.
Plot a labelled graph of |Vs| where Vs is stopping potential versus frequency f of the incident radiation. State how will you use this graph to determine the value of Planck's constant?
A police van moving on a highway with a speed of 30 km/h fires a bullet at a thief's car speeding away in the same direction with a speed of 192 km/h. If the muzzle speed of the bullet is 150 m is, with what speed does the bullet hit the thief's car?
In an inelastic collision, which of the following does not remain conserved?
According to Einstein's photoelectric equation, the plot of the kinetic energy of the emitted photoelectrons from a metal Vs the frequency of the incident radiation gives as straight the whose slope:
Einstein work on the photoelectric effect provided support for the eqn:-
Who indirectly determined the mass of the electron by measuring the charge of the electrons?
If the frequency of light in a photoelectric experiment is double the stopping potential will
If the energy of photon corresponding to a wavelength of 6000 A° is 3.32 × 10−19 J, the photon energy for a wavelength of 4000 A° will be ______.
What is the momentum of photon of energy 3 mev in kg ms-1?
Which of the following is/are true for cathode ray
The emission of electron is possible
(i) A ray of light incident on face AB of an equilateral glass prism, shows minimum deviation of 30°. Calculate the speed of light through the prism.
(ii) Find the angle of incidence at face AB so that the emergent ray grazes along the face AC.
- Calculate the energy and momentum of a photon in a monochromatic beam of wavelength 331.5 nm.
- How fast should a hydrogen atom travel in order to have the same momentum as that of the photon in part (a)?
Ultraviolet light is incident on metals P, Q and R, having work functions 8 eV, 2 eV and 4 eV respectively,
- Which metal has lowest threshold frequency for photoelectric effect?
- For which metal is the value of Emax minimum?
(Note: Emax is maximum kinetic energy of the emitted photoelectrons.)
How does stopping potential in photoelectric emission vary if the intensity of the incident radiation increases?
