Maximum kinetic energy is related to the incident frequency f and the threshold frequency f0 as:
Kmax=hf−hf0
When, f=2f0
21mv12=2hf0−hf0=hf0...(1)
When, f=5f0
21mv22=5hf0−hf0=4hf0...(2)
Hence, the ratio, v2v1=21
JEE Main 2023 — Physics Modern Physics
The threshold frequency of metal is f0. When the light of frequency 2f0 is incident on the metal plate, the maximum velocity of photoelectron is v1. When the frequency of incident radiation is increased to 5f0. the maximum velocity of photoelectrons emitted is v2. The ratio of v1 to v2 is:
Held on 1 Feb 2023 · Verified 6 Jul 2026.
v2v1=21
v2v1=81
v2v1=161
v2v1=41
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