CDS GK Questions 2026

Matheran, in the Raigad district of Maharashtra, is an eco-sensitive hill station where motor vehicles are not allowed within the town; visitors walk, ride horses or use hand-pulled carts, and the Matheran Hill Railway, a narrow gauge line from Neral, is the classic way to reach it.

The Karakoram Pass crosses the Karakoram range north of the Nubra valley and was the crucial crossing on the centuries-old caravan route that carried pashmina wool, silk and tea between Leh and Yarkand in Xinjiang.

The Lipulekh Pass lies in the Pithoragarh district of the Kumaon division and has long been the traditional Indian route for the Kailash Mansarovar pilgrimage, as well as an old trade crossing into Tibet.

Shimla, in Himachal Pradesh, was made the summer capital of British India in 1864, and the Government of India moved there from Calcutta and later Delhi every hot season; the narrow gauge Kalka to Shimla Railway that serves it was added to the Mountain Railways of India World Heritage site…

Khardung La lies on the Ladakh range just north of Leh and carries the road from Leh into the Nubra valley and on towards the Siachen area, which makes it one of the most strategically used high passes in the country.

The Mountain Railways of India World Heritage site is made up of three lines added in stages: the Darjeeling Himalayan Railway in West Bengal, inscribed in 1999, the Nilgiri Mountain Railway in Tamil Nadu, added in 2005, and the Kalka to Shimla Railway in Himachal Pradesh, added in 2008.

Mount Abu is the only hill station of Rajasthan and stands on an isolated block of the Aravalli range in the Sirohi district; Guru Shikhar, at about 1,722 metres, is the highest peak of the Aravalli and lies here, and the Dilwara Jain temples are nearby.

The Banihal Pass crosses the Pir Panjal range and is the historic gateway from Jammu into the Kashmir valley. Because the pass closes with snow, the Jawahar Tunnel was driven beneath it and opened in 1956, giving Jammu an all-weather road link with Srinagar.

Nathu La lies on the Sikkim border and crosses into the Chumbi valley of Tibet; it was an important wool and trade route, was closed after the 1962 conflict and was reopened for border trade in 2006.

The Palakkad Gap, also called the Palghat Gap, is about thirty kilometres wide and lies between the Nilgiris to its north and the Anaimalai hills to its south.

The Rohtang Pass lies on the Pir Panjal range in Himachal Pradesh and connects the Kullu valley with the Lahaul and Spiti district.

Nichrome is an alloy of nickel, chromium and iron with a high electrical resistance and a high melting point, and it does not oxidise easily when red hot, so a nichrome wire can glow for years without burning away; that combination makes it the standard material for the heating elements…

Limestone decomposes in the furnace to calcium oxide, a basic flux, which combines with the acidic silica gangue of the ore to form calcium silicate, a fusible slag that floats on the molten iron and is drawn off separately.

In the Mond process impure nickel is heated in a stream of carbon monoxide at a moderate temperature, forming the volatile compound nickel tetracarbonyl; the vapour is led away from the solid impurities and heated more strongly, whereupon it decomposes and deposits very pure nickel.

Galvanisation is the coating of iron or steel with zinc, usually by dipping it in molten zinc.

Pure alumina melts at a very high temperature, so in the Hall and Heroult process it is dissolved in molten cryolite, sodium hexafluoroaluminate, usually with some fluorspar, which lowers the working temperature of the bath and makes the melt a far better conductor of electricity.

German silver is an alloy of copper, zinc and nickel, and its name comes from its white silvery appearance, not from its composition, since it contains no silver at all; it is used for tableware, ornaments and electrical contacts.

Brass is made by alloying copper with zinc, which gives a metal harder than copper, easier to cast and machine, and resistant to ordinary corrosion, so it is used for utensils, taps and fittings and the bodies of musical instruments.

Zone refining rests on the fact that impurities are more soluble in a molten metal than in the same metal when solid.

Calcination is the heating of an ore in the absence or a limited supply of air and below its melting point, so that water of hydration and carbon dioxide are driven off; it is therefore the step used for carbonate ores such as calamine and for hydrated ores such as…