Question

An optical communication system is operating at a wavelength of $800nm$, its optical source frequency is

• A. $3.8\times {10}^{14}Hz$
• B. $3.8\times {10}^{12}Hz$
• C. $3.8\times {10}^{10}Hz$
• D. $3.8\times {10}^{9}Hz$

Answer 1

The correct option is A $3.8\times {10}^{14}Hz$

Since, it is optical communication, speed of the signals is equal to the speed of light.

Freq = speed of light/wavelength.

$f=\frac{3\times {10}^8}{800\times {10}^{-9}}=3.8\times {10}^{14}Hz$