JEE Main 2016PhysicsDual Nature of MatterMediumMCQ

JEE Main 2016Dual Nature of Matter Question with Solution

JEE Main 2016 (03 Apr)

Question

Radiation of wavelength λ is incident on a photocell. The fastest emitted photoelectron has a speed v. If the wavelength is changed to 3λ4, the speed of the fastest emitted photoelectron will be

Choose an option

Show full solutionCorrect option: C
Correct answer
C>v4312

Step-by-step explanation

12mv2=hcλ-ϕ ...(i)

12mv'2=43hcλ-ϕ  ...(ii)

From Eqn. (i)

hcλ=12mv2+ϕ

On putting this Equation (ii)

12mv2=4312mv2+ϕ-ϕ

v'2=43v2+2ϕ3m

v'>43v

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About this question

This is a previous-year question from JEE Main 2016, covering the Dual Nature of Matter chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.