According to Einstein's photoelectric effect,
KEmax=λhc−ϕ
The incident energy of the photon is E1=21mv2=hn−ϕ...(1)
If incident frequency increased to 3n
E2=21mv22=3hn−ϕ
=3(hn−ϕ)+2ϕ
E2=3E1+2ϕ
⇒21mv22=23mv2+2ϕ
⇒v22=3v2+m4ϕ
⇒v2>v3
JEE Main 2017 — Physics Modern Physics
The maximum velocity of the photoelectrons emitted from the surface is v when light of frequency n falls on a metal surface. If the incident frequency is increased to 3n, the maximum velocity of the ejected photoelectrons will be:
Held on 8 Apr 2017 · Verified 6 Jul 2026.
more than 3v
equal to 3v
v
less than 3v
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