Maximum kinetic energy is expressed as Kmax=hf−ϕ, here, ϕ is work function of metal.
For first case, 21mv12=h[(2f0)−f0]
For second case, 21mv22=h[(5f0)−f0]
⇒v12v22=14⇒v1v2=2
When light of frequency twice the threshold frequency is incident on the metal plate, the maximum velocity of emitted electron is v1. When the frequency of incident radiation is increased to five times the threshold value, the maximum velocity of emitted electron becomes v2. If v2=xv1, the value of x will be _____ .
Held on 24 Jun 2022 · Verified 6 Jul 2026.
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