CBSE 2024 · Region 3 · Set 1 · Q20 · 2 marks
The minimum intensity of white light that our eyes can perceive is about $\displaystyle 0.1 \mathrm{nWm}^{-2}$. Calculate the number of photons of this light entering our pupil (area $\displaystyle 0.4 \mathrm{~cm}^{2}$ ) per second. (Take average wavelength of white light $\displaystyle =500 \mathrm{~nm}$ and Planck's constant $\displaystyle =6.6 \times 10^{-34} \mathrm{Js}$ )
Marking-scheme solution
| \begin{tabular}[t]{|l|l|} Calculation of number of photons per second | $\displaystyle 2$ |
Dual Nature of Radiation and MatterParticle Nature of Light: The PhotonApplyvery_short_answermedium
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CBSE Class 12 Physics past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.