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प्रश्न
A non-monochromatic light is used in an experiment on photoelectric effect. The stopping potential
पर्याय
is related to the mean wavelength
is related to the longest wavelength
is related to the shortest wavelength
is not related to the wavelength
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उत्तर
is related to the shortest wavelength
For photoelectric effect to be observed, wavelength of the incident light `(λ)` should be less than the threshold wavelength `(λ_0)` of the metal .
Einstein's photoelectric equation :
`eV_0 = (hc)/(λ_0) - varphi`
Here, V0 = stopping potential
`λ_0` = threshold wavelength
h = Planck's constant
`varphi` = work-function of metal
It is clear from the above equation that stopping potential is related to the shortest wavelength (threshold wavelength).
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संबंधित प्रश्न
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point out any two characteristic properties of photons on which Einstein’s photoelectric equation is based ?
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Using Einstein’s photoelectric equation shows how the cut-off voltage and threshold frequency for a given photosensitive material can be determined with the help of a suitable plot/graph.
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(A) The saturation photocurrent remains almost the same.
(B) The maximum kinetic energy of the photoelectrons is doubled.
In a photoelectric experiment, the collector plate is at 2.0 V with respect to the emitter plate made of copper (φ = 4.5 eV). The emitter is illuminated by a source of monochromatic light of wavelength 200 nm. Find the minimum and maximum kinetic energy of the photoelectrons reaching the collector.
Use Einstein’s photoelectric equation to show how from this graph,
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Use Einstein's photoelectric equation to show how from this graph,
(i) Threshold frequency, and
(ii) Planck's constant can be determined.
The minimum energy required to remove an electron is called ______.
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 ______.
- In the explanation of photo electric effect, we assume one photon of frequency ν collides with an electron and transfers its energy. This leads to the equation for the maximum energy Emax of the emitted electron as Emax = hν – φ0 where φ0 is the work function of the metal. If an electron absorbs 2 photons (each of frequency ν) what will be the maximum energy for the emitted electron?
- Why is this fact (two photon absorption) not taken into consideration in our discussion of the stopping potential?
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:
