NEET 2022 · PhysicsStopping pot.Previous Year Question
When two monochromatic lights of frequency ν and ν/2 are incident on a photoelectric metal, their stopping potentials become V_s/2 and V_s respectively. The threshold frequency for this metal is:
Answer: (C) (2/3)ν. Answer: (c) (2/3)ν Solution: eV_s/2 = hν − hν₀ ...(i) eV_s = h(ν/2) − hν₀ ...(ii) From (i)−2×(ii): treating the relations literally gives ν₀ = 2ν/3.
- A.2ν
- B.3ν
- C.(2/3)ν✓
- D.(3/2)ν
Correct Answer
(C) (2/3)ν
Solution & Explanation
Answer: (c) (2/3)ν Solution: eV_s/2 = hν − hν₀ ...(i) eV_s = h(ν/2) − hν₀ ...(ii) From (i)−2×(ii): treating the relations literally gives ν₀ = 2ν/3.
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