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प्रश्न
Define the term: stopping potential in the photoelectric effect.
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उत्तर
The stopping potential is defined as the potential necessary to stop any electron from reaching the other side.
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संबंधित प्रश्न
If an electron has a wavelength, does it also have a colour?
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The photoelectric current increases with increase of intensity of incident light.
In photoelectric effect the photo current ______.
Consider a 20 W bulb emitting light of wavelength 5000 Å and shining on a metal surface kept at a distance 2 m. Assume that the metal surface has work function of 2 eV and that each atom on the metal surface can be treated as a circular disk of radius 1.5 Å.
- Estimate no. of photons emitted by the bulb per second. [Assume no other losses]
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- How much time would be required by the atomic disk to receive energy equal to work function (2 eV)?
- How many photons would atomic disk receive within time duration calculated in (iii) above?
- Can you explain how photoelectric effect was observed instantaneously?
