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A monochromatic light source of intensit...

A monochromatic light source of intensity 5 m W emits `(8xx10^15)` 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.

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Given `W_0 = hv - ev_0 `
`= 5 xx 10^(-3) / 8 xx 10^(15) - 1.6 xx 10^(-19) xx 2 `
` = 6.25 xx 10^(-19) - 3.2 xx 10^(-19) `
`= 3.05 xx 10^(-19)`
` 3.05 xx 10^(-19) / 1.6 xx 10^(-15) = 1.906 eV.`
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HC VERMA-PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY-Exercises
  1. Find the maximum kinetic energy of the photoelectrons ejected when lig...

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  2. The work function of a photoelectric material is 4.0 e V. (a) What i...

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  3. Find the maximum magnitude of the linear momentum of a photoelectron e...

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  4. When a metal plate is exposed to a monochromatic beam of light of wave...

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  5. In an experiment on photoelectric effect, the stopping potential is me...

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  6. The electric field associated with a monochromataic beam of light beco...

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  7. The electric field associated with a light wave is given by E= E0 sin...

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  8. The electric field at a point associated with a light wave is E=(100Vm...

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  9. A monochromatic light source of intensity 5 m W emits (8xx10^15) photo...

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  10. A photographic film is coated with a silver bromide layer. When light ...

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  11. In an experiment on photoelectric effect light of wavelength 400 nm is...

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  12. A silver ball of radius 4.8 cn is suspended by a thread in a cacuum ch...

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  13. In an experiment on photoelectric effect, the emitter and the collecto...

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  14. In the following arrangement y = 1.0 mm , d = 0.24 mm and D = 1.2 m. T...

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  15. In a photoelectric experiment, the collector plate is at 2.0 V with re...

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  16. A small piece of cesium metal(work function= 1.9eV) is kept at a dista...

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  17. Consider the situation of the previous problem. Consider the fastest e...

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  18. A horizontal cesium plate is moved vertically downward at a constant s...

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  19. A small metal plate of work function phi is kept at a distance r from ...

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  20. A light beam of wavelength 400 nm is incident on a metal of work- func...

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