JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
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
- A Both Cs and Li
- B Neither Cs nor Li
- C Cs only
- D Li only
Answer & Solution
Correct Answer
(C) Cs only
Step-by-step Solution
Detailed explanation
\(E=\frac{1240 \mathrm{eV} \cdot \mathrm{~nm}}{550 \mathrm{~nm}}=2.25 \mathrm{eV}\) Possible for \(C_s\) as \(E > \phi_{c s}\) Not for Li as \(E < \phi_{L i}\)
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