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JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
When a certain photosensitive surface is illuminated with monochromatic light of frequency \(v\) , the stopping potential for the photo current is \(-V_0/2.\) When the surface is illuminated by monochromatic light of frequency \(v/2,\) the stopping potential is \(-V_0.\) The threshold frequency for photoelectric emission is
- A \(\frac {5v}{3}\)
- B \(\frac {4}{3}\,v\)
- C \(2\,v\)
- D \(\frac {3v}{2}\)
Answer & Solution
Correct Answer
(D) \(\frac {3v}{2}\)
Step-by-step Solution
Detailed explanation
\({\text{e}}{{\text{V}}_{\text{s}}} = {\text{hv}} - \phi \) \(\left\{ {\frac{{ - e{V_0}}}{2} = hv - \phi } \right\} \times 2\) ..... \((1)\) \( - e{V_0} = \frac{{hv}}{2} - \phi \) ..... \((2)\) \(0 = 2hv - 2\phi - \frac{{hv}}{2} + \phi \) \(\phi = \frac{{3hv}}{2}\)…
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