AP EAMCET · PHYSICS · Dual Nature of Matter
A laser produces a beam of light of frequency \(5 \times 10^{14} \mathrm{~Hz}\) with an output power of 33 mW. The average number of photons emitted by the laser per second is \(\left(\right.\) Planck's constant \(\left.=6.6 \times 10^{-34} \mathrm{~J} \mathrm{~s}\right)\)
- A \(40 \times 10^{16}\)
- B \(10 \times 10^{16}\)
- C \(30 \times 10^{16}\)
- D \(20 \times 10^{16}\)
Answer & Solution
Correct Answer
(B) \(10 \times 10^{16}\)
Step-by-step Solution
Detailed explanation
\(E = h\nu\) \(E = (6.6 \times 10^{-34}) \times (5 \times 10^{14}) = 33 \times 10^{-20} \mathrm{~J}\) \(N = P/E\) \(N = (33 \times 10^{-3}) / (33 \times 10^{-20}) = 1 \times 10^{17} = 10 \times 10^{16}\)
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Codes
\(\begin{array}{llll}
A & B & C & D
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