KEmax=λhc−ϕ=500hc−ϕ .....(i)
Now,
3KEmax=200hc−ϕ
.....(ii)
From equation (i) and (ii)
(i)(ii)=13=500hc−ϕ200hc−ϕ
Put the value of hc=1237.5 and solving ϕ=0.61eV
When the wavelength of radiation falling on a metal is changed from 500nmto200nm, the maximum kinetic energy of the photoelectrons becomes three times larger. The work function of the metal is close to:
Held on 3 Sept 2020 · Verified 6 Jul 2026.
0.81eV
1.02eV
0.52eV
0.61eV
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