E=550 nm1240eV⋅ nm=2.25eV Possible for Cs as E>ϕcs Not for Li as E<ϕLi
JEE Main 2025 — Physics Modern Physics
The work functions of cesium (Cs) and lithium (Li) metals are 1.9 eV and 2.5 eV , respectively. If we incident a light of wavelength 550 nm on these two metal surfaces, then photo-electric effect is possible for the case of
Held on 22 Jan 2025 · Verified 6 Jul 2026.
Both Cs and Li
Neither Cs nor Li
Cs only
Li only
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