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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): Photosensitivity of a metal is high if its work function is small.
Reason (R): Work function $=\text{h}\upsilon_0,$ where $\upsilon_0$ is the threshold frequency.
✓

Answer

  1. Both A and R are true but R is NOT the correct explanation of A.
Explanation:

Less work function means less energy is required for ejecting out the electrons.

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