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

Hint Understand the meaning behind optical communication. Optical communication involves light rays for transferring of messages. Now, directly find the frequency by dividing the speed of light rays with the given wavelength.

Complete Step By Step Solution
Optical communication is a type of communication method, which uses light rays to carry information. Optical fibers are required to transmit light rays constantly throughout for a larger distance. Since the speed of light is greater than speed of sound or speed of radio waves, optical communication is said to be the fastest communication mode. It is also understandable that the construction of optical fibre cables are robust, which makes optical communication much more secure than others.
It is given that the optical communication system is operating at a given wavelength of \[800nm\]. We need to find out the frequency of the optical source. We know that , frequency is given by the formula,
\[f = \dfrac{c}{\lambda }\], where c is the speed of light and \[\lambda \]is the wavelength of the light ray passed.
Substituting the wavelength value in the above equation we get,
\[ \Rightarrow f = \dfrac{{3 \times {{10}^8}}}{{800 \times {{10}^{ - 9}}}}\]
On simplifying this equation we get,
\[ \Rightarrow f = \dfrac{{3 \times {{10}^{15}}}}{8}\]
\[ \Rightarrow f = 3.8 \times {10^{14}}Hz\]

Thus, option (A) is the right answer for the given question.

Note
An optical wave is a type of electromagnetic wave that has the ability to propagate in free space and also can be guided with dielectric. The optical waves undergo the concept of total internal reflection inside an optical fiber cable between the core and the cladding part of the cable. The optical communication has a wide range of electromagnetic spectrum, enabling it to be deployed in large distance communication.