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JEE Main202120 Jul 2021Evening ShiftPhysicsDual Nature of MatterActual

A certain metallic surface is illuminated by monochromatic radiation of wavelength . The stopping potential for photoelectric current for this radiation is 3 V 0 . If the same surface is illuminated with a radiation of wavelength 2 λ , the stopping potential is V 0 . The threshold wavelength of this surface for photoelectric effect is___________ λ .

Correct answer

0

Step-by-step solution

KE = h c λ - ϕ h c e 3 V 0 = h c λ 0 - ϕ     … i e V 0 = h c 2 λ 0 - ϕ     … ii Using i  and   ii , ϕ = h c 4 λ 0 = h c λ t λ t = 4 λ 0

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