With reference to 'LiFi', recently in the news, which of the following statements is/are correct? 1. It uses light as the medium for high-speed data transmission. 2. It is a wireless technology and is several times faster than 'WiFi'. Select the correct answer using the code given below.
- (a) 1 only
- (b) 2 only
- (c) Both 1 and 2 ✓ UPSC's answer
- (d) Neither 1 nor 2
Why the answer is (c)
• Li-Fi (Light Fidelity) transmits data by modulating visible light from LEDs at speeds imperceptible to the eye (statement 1).
• It is wireless, and laboratory tests have reached over 200 Gbps — many times faster than Wi-Fi — though it needs line of sight and cannot pass through walls (statement 2).
• It was in the news in 2015–16 after Estonian office trials.
• Hence both 1 and 2, option (c).
Why the other options are wrong
- (a) 1 only
- Statement 2 is also correct: Li-Fi is wireless and faster than Wi-Fi.
- (b) 2 only
- Statement 1 is also correct: it uses light.
- (d) Neither 1 nor 2
- Both statements are correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2016, held on 7 August 2016. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.