JEE Mains · Chemistry · STD 11 - 2. structure of atom
If \(p\) is the momentum of the fastest electron ejected from a metal surface after the irradiation of light having wavelength \(\lambda \), then for \(1.5\, p\) momentum of the photoelectron, the wavelength of the light should be: (Assume kinetic energy of ejected photoelectron to be very high in comparison to work function)
- A \(\frac{3}{4}\lambda \)
- B \(\frac{1}{2}\lambda \)
- C \(\frac{4}{9}\lambda \)
- D \(\frac{2}{3}\lambda \)
Answer & Solution
Correct Answer
(C) \(\frac{4}{9}\lambda \)
Step-by-step Solution
Detailed explanation
\(K.E = \frac{1}{2}m{u^2} = \frac{1}{2}\frac{{{m^2}{u^2}}}{m} = \frac{1}{2}\frac{{{P^2}}}{m}\) \(\frac{{hc}}{{{\lambda _1}}} = Wo + {(K.E)_1} = Wo + \frac{1}{2}\frac{{{P^2}}}{m}\) \(\frac{{hc}}{{{\lambda _2}}} = Wo + {(K.E)_2} = Wo + \frac{1}{2}\frac{{{{(1.5P)}^2}}}{m}\) On…
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