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It has been determined experimentally th...

It has been determined experimentally that when light falls on a metal surface, the surface emits electrons. For example, you can start a current in a circuit just by shining a light on a metal plate.

a. What is your explanation?
b. Mention some other methods in which electron emission is possible.
c. Are stopping potential and cut off potential the same?

Text Solution

Verified by Experts

a. The electrons in the metal surface absorb photon energy and are emitted.
b. Thermionic emission, photoelectric effect, field emission, secondary emission.
c. Yes
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NEW JOYTHI PUBLICATION-DUAL NATURE OF RADIATION AND MATTER -EVALUATION QUESTIONS AND ANSWERS
  1. Fill in the blanks.

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  2. Match the following

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  3. It has been determined experimentally that when light falls on a metal...

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  4. a. Draw the graph showing the variation of potential with frequency of...

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  5. An image of the sun is formed on the metal surface of the photoelectri...

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  6. All the photoelectrons are not emitted with same energy. Give reason.

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  7. Light is incident on the cathode of a photocell and the stopping volt...

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  8. The graph shows the variation of photoelectric current with accelerati...

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  9. Find the effective capacity of the combination shown below :

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  10. The above graph shows frequency of an incident photon and maximum kine...

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  11. a. What is the purpose of Cu(2)? b. Which plate becomes positive? ...

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  12. a. Why de-Broglie wave associated with a moving car is not visible ? ...

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  13. a. Give the expression showing the relation between energy and moment...

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  14. a. The wave nature of matter is not noticeable in our daily observati...

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  15. What do the graphs represent?

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  16. Which of the following statements are is not correct about a photon?

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  17. a. Every metal has a definite work function. Why all photoelectrons ...

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  18. Eventhough metals have free electrons, they cannot escape from metal ...

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  19. Define 1 eV.

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  20. What are the factors on which the rate of thermionic emission depends?

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