UPSC Prelims 2020 - Question 39

Here is Question No. 39 a part of our series on UPSC Prelims 2020.

Table of Contents

Select the correct answer using the code given below
(a) 1, 2 and 3 only
(b) 1, 2 and 4 only
(c) 1, 3 and 4 only
(d) 2, 3 and 4 only

Answer: C

Visible Light Communication (VLC) technology is a wireless communication technology that utilizes light to transmit data and position between devices.
Statement 1 is correct: Li-Fi is a Visible Light Communications (VLC) system. Visible Light Communication (VLC) systems employ visible light for communication that occupy the electromagnetic spectrum from 375 nm to 780 nm.
Statement 2 is not correct: Long-range links are provided by optical fibre (also known as fiber optic cables), and links from the long-range end-points to end users are accomplished by RF wireless not by VLC.
Statement 3 is correct: VLC can transmit large amounts of data faster than Bluetooth. The VLC uses visible light for communication to provide high-speed internet up to 10 Gb/s while Bluetooth 4.0 promises speeds up to 25 Mb/s.
Statement 4 is correct: Without causing electromagnetic interference VLC has the advantage of being useful in electromagnetic-sensitive areas such as in aircraft cabins, hospitals, and nuclear power plants