UPSC 2016 Previous Year GK Questions with Answers

The correct answer is B, plan of action outlined by the countries of the world to combat climate change. INDCs were the climate pledges countries announced before the Paris climate conference of 2015.

Under the UN Framework Convention on Climate Change, each country was asked to state what it intended to do to cut greenhouse gas emissions and adapt to climate change after 2020. These Intended Nationally Determined Contributions were submitted before COP21 in Paris in December 2015. Once a country ratified the Paris Agreement, its INDC became its Nationally Determined Contribution (NDC), to be updated every five years with greater ambition. India's first INDC was submitted in October 2015.

A is wrong because refugee pledges have nothing to do with this term.

C is wrong because capital subscriptions to the AIIB are not called INDCs.

D is wrong because the Sustainable Development Goals are pursued through the 2030 Agenda, not through INDCs.

Exam tip: INDC before Paris (COP21, 2015) became NDC after ratification, revised every five years.

The correct answer is C, Both 1 and 2. LiFi (Light Fidelity) sends data wirelessly by switching LED light on and off far too fast for the eye to notice, and it can be many times faster than WiFi.

The idea was popularised by Professor Harald Haas of the University of Edinburgh in 2011. A LiFi bulb flickers at very high frequency, and a photodetector reads these changes as binary data. Because visible light has a far wider spectrum than the radio waves used by WiFi, laboratory tests have reached speeds many times higher than WiFi. Light cannot pass through walls, which limits range but makes the signal harder to intercept and free of radio interference, useful in hospitals and aircraft.

A is wrong because statement 2 is also correct.

B is wrong because statement 1, the use of light, is the very basis of LiFi.

D is wrong because both statements describe LiFi correctly.

Exam tip: WiFi uses radio waves; LiFi uses visible light from LEDs and cannot pass through walls.

The correct answer is D, boric acid. Boric acid dissolves in water to give a true solution, in which the dispersed particles are individual molecules small enough to pass through a filter paper and even a parchment membrane, and the mixture shows no Tyndall effect. A true solution is therefore not a colloid.

Option A is wrong because milk is a colloid, an emulsion of liquid fat droplets dispersed in water. Option B is wrong because mud is a colloidal dispersion of fine soil particles in water, which is why it stays turbid for a long time before settling. Option C is wrong because butter is also a colloid, with water dispersed in fat, that is a gel-like emulsion. The rule to apply is that only a true solution is excluded from the colloidal state.