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A photoelectric cell is illuminated by a...

A photoelectric cell is illuminated by a point source of light `1m` away. When the source us shifted to `2m` then-

A

each emitted electron carries one quarter of the initial energy

B

number of electrons emitted is half the initial number

C

each emitted electron carries half the initial energy

D

number of electrons emitted is a quarter of the initial number

Text Solution

Verified by Experts

The correct Answer is:
D
`:' I prop (1)/(r^(2)) :.` intensity becomes `1/4` th
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ALLEN -SIMPLE HARMONIC MOTION-Exercise-01
  1. Photoelectric effect takes place in element A. Its work function is 2....

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  2. A certain metallic surface is illuminated with monochromatic light of ...

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  3. A photoelectric cell is illuminated by a point source of light 1m away...

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  4. A photosensitive metallic surface has work funtion hv(0). If photons o...

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  5. The half life of radioactive Radon is 3.8 days . The time at the end o...

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  6. Radiation of wavelength lambda is incident on a photocell.The fastest ...

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  7. An impluse laser may be treaed as a source of phtons that are emitted ...

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  8. 1.5 mW of 400 nm light is directed at a photoelectric cell. If 0.1% of...

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  9. Let K(1) be the maximum kinetic energy of photoelectrons emitted by a ...

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  10. In a photoelectric emission, electrons are ejected from metals X and Y...

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  11. White light consisting of wavelengths 380 nm le lambda le 750 nm is in...

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  12. The de Broglie waves are associated with moving particles. These parti...

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  13. Which of the following statements is wrong?

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  14. Two paricles have idential charges. If they are accelerated throgh sam...

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  15. Linear momenta of a proton and an electrons are euqal. Then

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  16. The wavelength of de-Brogile waves associted with neutrons at room tem...

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  17. Light coming from a discharge tube filled with hydrogen falls on the c...

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  18. If elements with principal quantum number ngt 4 were not allowed in na...

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  19. If 13.6 eV energy is required to ionized the hydrogen atom, then the e...

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  20. The diagram shows the energy levels for an electron in a certain atom....

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