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
Solution
<p>For photo-electric effect, energy of the photon must be greater than the work function of the metal.</p>
<p>We know, $E = {{1240} \over \lambda } = {{1240} \over {550}}$ (as $\lambda=550$ nm given)</p>
<p>$\Rightarrow E=2.25$ eV</p>
<p>here, $E > {\phi _{cs}}$</p>
<p>So, $C_S$ only.</p>
About this question
Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect
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