COMEDK · Physics · 27. Dual Nature of Matter
If \(K_1\) and \(K_2\) are maximum kinetic energies of photoelectrons emitted when lights of wavelengths \(\lambda_1\) and \(\lambda_2\), respectively incident on a metallic surface and \(\lambda_1=3 \lambda_2\), then
- A \(K_1>\left(\dfrac{K_2}{3}\right)\)
- B \(K_1 < \left(\dfrac{K_2}{3}\right)\)
- C \(K_1=2 K_2\)
- D \(K_2=2 K_1\)
Answer & Solution
Correct Answer
(B) \(K_1 < \left(\dfrac{K_2}{3}\right)\)
Step-by-step Solution
Detailed explanation
According to Einstein's photoelectric equation, the maximum kinetic energy \(K\) of emitted photoelectrons is given by \(K = \dfrac{hc}{\lambda} - \phi\), where \(\phi\) is the work function of the metal. For the first wavelength \(\lambda_1\),…
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