de-Broglie wavelength: $\lambda = \frac{h}{p} = \frac{h}{\sqrt{2mqV}}$ For the same potential difference (V), $\lambda \propto \frac{1}{\sqrt{mq}}$.
$\frac{\lambda_a}{\lambda_e} = \sqrt{\frac{m_e q_e}{m_a q_a}}$
Since $m_a >> m_e$ and $q_a = 2q_e$, $\lambda_e > \lambda_a$.
The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are 2.14eV, 2.30 eV and 2.75eV respectively. If incident electromagnetic radiation has an incident energy of 2.20eV, which of these photosensitive surfaces may emit photoelectrons?
List I | List II | ||
---|---|---|---|
A | Mesozoic Era | I | Lower invertebrates |
B | Proterozoic Era | II | Fish & Amphibia |
C | Cenozoic Era | III | Birds & Reptiles |
D | Paleozoic Era | IV | Mammals |