Question

Bandwidth of an optical fiber is
$$\begin{gathered} \text{A})More\text{ than 100GHz} \\ \text{B)Few kHz} \\ \text{C)less than 1MHz} \\ \text{D)less than 1GHz} \end{gathered}$$

Answer 1

Hint- In order to solve this question, we must know the concept of optical fiber, its types and its bandwidth. Then we will compare the different bandwidth given as options to find the required bandwidth of an optical fiber.

Complete step-by-step answer:
An optical fiber is a lightweight and transparent fiber produced using silica or plastic expelled glass, which is somewhat thicker than an individual's hair. It is able to transmit light between the two ends.At its entry points, light can be coupled only to a fiber.
By tracking the actual power transmission, an optical fiber which is broken or damaged can be detected extremely fast.
As the dispersion effect increases with the length of the fiber, its bandwidth-distance product, usually expressed in km of MHz, often characterizes a transmission system.
This value is a product of bandwidth and distance because there is a trade-off between the bandwidth and distance over which it can be carried. A multi-mode optical fiber has a larger core. The speed of fiber optic cable is 10/100/1000 Mbps, 10/40/100/200Gbps.
A multi-mode fiber, however, introduces multimode distortion which frequently limits the bandwidth and length of the connection.
Two key types of optical fiber used in optical communications include optical multi-mode fibers and optical single-mode fibres.
As in earlier times, coaxial cables were used which had bandwidth in KHz, so option B and C becomes irrelevant.
Multimode optical fiber can readily transmit high bandwidth data over long distances; a typical bandwidth-distance product for multimode fiber is 500MHz/km could carry , so a 500m tether can transmit 1GHz (several Gigabytes /second, with appropriate modulation). Signal losses over 500 m are negligible; signal dispersion limits the bandwidth.But for higher bandwidth, it depends on the router. So it can be more than 100GHz.
Therefore, we conclude that the Bandwidth of an optical fiber is more than 100GHz.
Hence, option A is correct.

Note- While solving this question, we must know that the speed of fiber optic cable is 10/100/1000 Mbps, 10/40/100/200Gbps. A multi-mode optical fiber has a larger core. Also one must know the several types of cables (fiber optic cable, twisted pair cable, coaxial cable) to solve similar questions.