JEE Mains · Chemistry · STD 11 - 2. structure of atom
A \(50\, watt\) bulb emits monochromatic red light of wavelength of \(795\, \mathrm{~nm}\). The number of photons emitted per second by the bulb is \(\mathrm{x} \times 10^{20}\). The value of \(\mathrm{x}\) is ...... . \(\left[\right.\) Given \(: \mathrm{h}=6.63 \times 10^{-34} \,\mathrm{Js}\) and \(\left.\mathrm{c}=3.0 \times 10^{8} \,\mathrm{~ms}^{-1}\right]\)
- A \(1\)
- B \(4\)
- C \(2\)
- D \(3\)
Answer & Solution
Correct Answer
(C) \(2\)
Step-by-step Solution
Detailed explanation
Total energy per sec. \(=50\, \mathrm{~J}\) \(50=\frac{\mathrm{n} \times 6.63 \times 10^{-34} \times 3 \times 10^{8}}{795 \times 10^{-9}}\) \(\mathrm{n}=1998.49 \times 10^{17}[\mathrm{n}=\mathrm{no} .\) of photons per second \(]\) \(=1.998 \times 10^{20}\)…
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