COMEDK · Physics · 30. Semiconductors
An optical fibre communication system works on a wavelength of \(1.3 \mu \mathrm{m}\). The number of subscribers it can feed, if a channel requires \(20 \mathrm{kHz}\) are
- A \(23 \times 10^{10}\)
- B \(1.15 \times 10^{10}\)
- C \(1 \times 10^{5}\)
- D None of these
Answer & Solution
Correct Answer
(B) \(1.15 \times 10^{10}\)
Step-by-step Solution
Detailed explanation
The frequency of the optical signal is given by \(\nu = \dfrac{c}{\lambda}\), where \(c = 3 \times 10^8 \text{ m/s}\) and \(\lambda = 1.3 \times 10^{-6} \text{ m}\). \(\nu = \dfrac{3 \times 10^8}{1.3 \times 10^{-6}} \approx 2.3 \times 10^{14} \text{ Hz}\). The number of…
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