﻿ Light of wavelength 3500 Å is incident on two metals A and B. Which metal will emit photoelectrons, if their work functions are 4.2 eV and 1.9 eV respectively?  : Kaysons Education

# Light Of Wavelength 3500 Å Is Incident On Two Metals A and B. Which Metal Will Emit Photoelectrons, If Their Work Functions Are 4.2 EV And 1.9 EV Respectively?

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## Question

### Solution

Correct option is

Metal B, 3.54 eV

The energy of incident light photon of wavelength

is

= 3.54 eV.

The incident light will yield photoelectrons if its energy is greater than the work function of the metal. Thus, metal B(W = 1.9 eV) will emit photoelectrons.

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