JEE Main 2026 · Session 2 · Shift 1 · Physics
Question 42
For a certain metal, when monochromatic light of wavelength λ is incident, the stopping potential for photoelectrons is 3V₀. When the same metal is illuminated by light of wavelength 2λ, then the stopping potential becomes V₀. The threshold wavelength for photoelectric emission for the given metal is αλ. The value of α is ____.
- A. 1
- B. 4Correct answer
- C. 2
- D. 3
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Official source
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Question paper, page 17.