JEE Main 2019PhysicsDual Nature of MatterEasyMCQ

JEE Main 2019 — Dual Nature of Matter Question with Solution

JEE Main 2019 (12 Apr Shift 1)

Question

The stopping potential Vo (in volt) as a function of frequency (v) for a sodium emitter, is shown in the figure. The work function of sodium, form the data plotted in the figure, will be:
(Given: Planck’s constant h=6.63×10-34 J s , electron charge ( e ) =1.6×10-19 C)

Choose an option

Show full solutionCorrect option: D
Correct answer
D1.66 eV

Step-by-step explanation

From Einstein's photoelectric equation, hν=ϕ+eV0  .

⇒V0=hνe-ϕe  ......1

At ν=4×1014 Hz, V0=0.

Putting the value in equation 1, we get

 0=hve-ϕe

So, Work function (ϕ)=hνe  in eV
=6.63×10-34×4×10141.6×10-19
=1.66 eV

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About this question

This is a previous-year question from JEE Main 2019, 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.