JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
\(K_1\) and \(K_2\) be the maximum kinetic energies of photoelectrons emitted from a surface of a given material for the light of wavelength \(\lambda_1\) and \(\lambda_2\), respectively. If \(\lambda_1=2\lambda_2\) then the work function of material is given by:
- A \(K_2+2K_1\)
- B \(2K_2-K_1\)
- C \(K_1-2K_2\)
- D \(K_2-2K_1\)
Answer & Solution
Correct Answer
(D) \(K_2-2K_1\)
Step-by-step Solution
Detailed explanation
Using Einstein's photoelectric equation: \(K_1 = \dfrac{hc}{\lambda_1} - \phi\) \(K_2 = \dfrac{hc}{\lambda_2} - \phi\) Given \(\lambda_1 = 2\lambda_2\), the first equation becomes: \(K_1 = \dfrac{hc}{2\lambda_2} - \phi\) Multiplying by \(2\):…
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