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प्रश्न
Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.
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उत्तर
Hence, it follows that as `1/lambda` increases, V0 increases.
The plot of V0 verses `1/lambda` is linear. This is due to the fact that the energy associated with a quantum of radiation (photon) is directly proportional to its frequency and thus inversely proportional to its wavelength of radiation.
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संबंधित प्रश्न
Using the values of work function given in the following table, tell which metal will require the highest frequency of incident radiation to generate photocurrent.
Typical values of work function for some common metals
| Metal | Work function (in eV) |
| Potassium | 2.3 |
| Sodium | 2.4 |
| Calcium | 2.9 |
| Zinc | 3.6 |
| Silver | 4.3 |
| Aluminium | 4.3 |
| Tungsten | 4.5 |
| Copper | 4.7 |
| Nickel | 5.0 |
| Gold | 5.1 |
Photocurrent recorded in the microammeter in an experimental setup of the photoelectric effect vanishes when the retarding potential is more than 0.8 V if the wavelength of incident radiation is 4950 Å. If the source of incident radiation is changed, the stopping potential turns out to be 1.2 V. Find the work function of the cathode material and the wavelength of the second source.
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Explain the concept of the photoelectric effect.
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v = 5v0?
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(h = Planck's constant, c =velocity of light)
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(Mass of electron = 9.1 × 10-31 kg)
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(h = 6.63 × 10-34 Js, c = 3 × 108 ms-1)
The radiation emitted, when an electron jumps from n = 3 to n = 2 orbit is a hydrogen atom, falls on a metal to produce photoelectron. The electrons from the metal surface with maximum kinetic energy are made to move perpendicular to a magnetic field of `1/320`T in a radius of 10-3m. Find the 320 work function of metal:
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Define photoelectric work function of a metal.
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According to Einstein's photoelectric equation, the graph of kinetic energy of the photoelectron emitted from the metal versus the frequency of incident radiation gives a straight line graph whose slopе ______.
