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Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter1 Mark
Question
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions front the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): On increasing the frequency of light, larger number of photoelectrons are emitted.
Reason (R): The number of electrons emitted is directly proportional to the intensity of incident light.
✓

Answer

  1. A is false and R is also false.
Explanation:

The maximum kinetic energy of the photoelectrons varies linearly with the frequency of incident radiation, but is independent of its intensity. The number of photoelectrons emitted per second is directly proportional to the intensity of incident radiation.

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