Advertisements
Advertisements
Question
Write the basic features of photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based.
Solution
Photon picture of electromagnetic radiation on which Einstein’s photoelectric equation is based on particle nature of light. Its basic features are:
(i) In interaction with matter, radiation behaves as if it is made up of particles called photons.
(ii) Each photon has energy E (=hν) and momentum p (=hν/c), and speed c, the speed of light.
(iii) All photons of light of a particular frequency ν, or wavelength λ, have the same energy E (=hν=hc/λ) and momentum p (=hν/c=h/λ), whatever the intensity of radiation may be.
(iv) By increasing the intensity of light of given wavelength, there is only an increase in the number of photons per second crossing a given area, with each photon having the same energy. Thus, photon energy is independent of intensity of radiation.
(v) Photons are electrically neutral and are not deflected by electric and magnetic fields.
(vi) In a photon-particle collision (such as photon-electron collision), the total energy and total momentum are conserved. However, number of photons may not be conserved.
APPEARS IN
RELATED QUESTIONS
A proton and a deuteron are accelerated through the same accelerating potential. Which one of the two has less momentum?
Give reasons to justify your answer.
The work function for a metal surface is 2.2eV. If the light of wavelength 5000Å is incident on the surface of the metal, find the threshold frequency and incident frequency. Will there be an emission of photoelectrons or not? (c = 3 x 108 m/ s, 1eV = 1.6x10-19 J , h = 6.63 x 10-34 J.s.)
Einstein's photoelectric equation is:
a) `E_"max" = hlambda - varphi_0`
b) `E_"max"= (hc)/lambda varphi_0`
c) `E_"max" = hv + varphi_0`
d) `E_"max" = (hv)/lambda + varphi_0`
With reference to the photoelectric effect, define threshold wavelength
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 = ______.
Threshold frequency for photoelectric effect on sodium corresponds to a wave length 5000. Its work function is ______.
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
The emission of electron is possible
The moment of a photon is given by
How does stopping potential in photoelectric emission vary if the intensity of the incident radiation increases?