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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

Options

  1. ABoth Cs and Li
  2. BNeither Cs nor Li
  3. CCs only
  4. DLi only

Correct answer

C. Cs only

Step-by-step solution

(E= 1240 eV ~nm 550 ~nm =2.25 eV ) Possible for (C_s ) as (E > _ c s ) Not for Li as (E < _ L i )

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