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

Rajasthan 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): Work function of aluminium is 4.2eV. Emission of electrons will not be possible if two photons each of energy 2.5eV strike an electron of aluminium.
Reason (R): For photoelectric emission the energy of each photon should be greater than the work function of aluminium.
✓

Answer

  1. Both A and R are true and R is the correct explanation of A.
Explanation:
This is because the probability is very low for two photons of energy 2.5eV making a collision with the same electron in the metal simultaneously.

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