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प्रश्न
How does one explain the emission of electrons from a photosensitive surface with the help of Einstein’s photoelectric equation?
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उत्तर १
Einstein’s Photoelectric equation is
KEmax = hv - hv0
eV0 = h(v - v0)
From above equation
Case - I:
If v > v0 [Emission with K.E.]
If v = v0 [Just emission]
If v < v0 [No emission]
उत्तर २
Einstein's photoelectric equation is, K. E = hv - Φ or hv = Φ + K. E.
This equation explains that when a photon of certain energy is incident on a photosensitive surface, a particular amount of energy gets used as a work function to eject electrons from their shells and the rest of the energy is acquired by ejected electrons as their Kinetic energy. The emission of electrons from a photosensitive surface takes place only if the incident energy of photons is greater than the work function.
संबंधित प्रश्न
In an experiment on the photoelectric effect, the slope of the cut-off voltage versus the frequency of incident light is found to be 4.12 × 10−15 Vs. Calculate the value of Planck’s constant.
point out any two characteristic properties of photons on which Einstein’s photoelectric equation is based ?
Briefly explain the three observed features which can be explained by Einstein’s photoelectric equation.
The electric field at a point associated with a light wave is `E = (100 "Vm"^-1) sin [(3.0 xx 10^15 "s"^-1)t] sin [(6.0 xx 10^15 "s"^-1)t]`.If this light falls on a metal surface with a work function of 2.0 eV, what will be the maximum kinetic energy of the photoelectrons?
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
A monochromatic light source of intensity 5 mW emits 8 × 1015 photons per second. This light ejects photoelectrons from a metal surface. The stopping potential for this setup is 2.0 V. Calculate the work function of the metal.
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
Consider the situation of the previous problem. Consider the faster electron emitted parallel to the large metal plate. Find the displacement of this electron parallel to its initial velocity before it strikes the large metal plate.
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
Use Einstein's photoelectric equation to show how from this graph,
(i) Threshold frequency, and
(ii) Planck's constant can be determined.
The wavelength of a photon needed to remove a proton from a nucleus which is bound to the nucleus with 1 MeV energy is nearly ______.
There are materials which absorb photons of shorter wavelength and emit photons of longer wavelength. Can there be stable substances which absorb photons of larger wavelength and emit light of shorter wavelength.
A student performs an experiment on photoelectric effect, using two materials A and B. A plot of Vstop vs ν is given in Figure.
- Which material A or B has a higher work function?
- Given the electric charge of an electron = 1.6 × 10–19 C, find the value of h obtained from the experiment for both A and B.
Comment on whether it is consistent with Einstein’s theory:
