JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
Light source having wavelength \(331\) nm is used to generate photo-electrons whose stopping potential is \(0.2\) V. The work function of the used metal in the experiment is \(\alpha \times 10^{-19}\) J. The value of \(\alpha\) is _____.
(\(h = 6.62 \times 10^{-34}\) J s, \(e = 1.6 \times 10^{-19}\) C and \(c = 3 \times 10^8\) m/s)
- A \(3.68\)
- B \(4.68\)
- C \(5.68\)
- D \(2.68\)
Answer & Solution
Correct Answer
(C) \(5.68\)
Step-by-step Solution
Detailed explanation
Using Einstein's photoelectric equation: \(\dfrac{hc}{\lambda} = \Phi + eV_0\) The energy of the incident photon is: \(E = \dfrac{hc}{\lambda} = \dfrac{6.62 \times 10^{-34} \times 3 \times 10^8}{331 \times 10^{-9}}\)…
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