JEE Main 2014 — Dual Nature of Matter Question with Solution
JEE Main 2014 (12 Apr Online)
Question
A beam of light has two wavelengths of and with a total intensity of equally distributed among the two wavelengths. The beam falls normally on an area of of a clean metallic surface of work function . Assume that there is no loss of light by reflection and that each capable photon ejects one electron. The number of photoelectrons liberated in is approximately:
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
Given,
and
and
Intensity associated with each wavelength
Work function
for different wavelengths
Work function for metallic surface (given)
Therefore, will not contribute in this process.
Now, no. of electrons per no. of photons per
no. of electrons per
So, the number of photo electrons liberated
in 2 sec.
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This is a previous-year question from JEE Main 2014, 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.