Expression for maximum kinetic energy can be written as, (KE)max=E−ϕ
(KE)max,1=E1−ϕ=3.8−0.6=3.2eV, (KE)max,2=E2−ϕ=1.4−0.6=0.8eV
(KE)max,2(KE)max,1=0.83.2=4⇒4=21mv2221mv12
⇒v22v12=4 ⇒v2v1=2:1
The light of two different frequencies whose photons have energies 3.8eV and 1.4eV respectively, illuminate a metallic surface whose work function is 0.6eV successively. The ratio of maximum speeds of emitted electrons for the two frequencies respectively will be :
Held on 24 Jun 2022 · Verified 6 Jul 2026.
2:1
4:1
1:2
1:4
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