NDA GK Questions 2026

An isohel, from the Greek helios for the sun, joins places that receive sunshine for an equal number of hours, and such maps are used in studies of solar energy potential and of crop seasons.

The word comes from the Greek hyetos, meaning rain, so an isohyet joins all places on a map that receive the same amount of rainfall in a given period; rainfall distribution maps of India, which show the 200 centimetre and 50 centimetre lines, are drawn with isohyets.

The deeply indented coast of Kutch and Saurashtra, with the Gulf of Kachchh and the Gulf of Khambhat, gives Gujarat the longest coastline of any Indian state, ahead of Andhra Pradesh and Tamil Nadu.

These are the latitudes of the southern tip of the mainland at Kanyakumari and of the northernmost part of the country, and between them lie the 3,214 km of the mainland's north-south extent.

The correct answer is C, Bangladesh, with which India shares a border of about 4,096.7 km, the longest of all its land boundaries; it touches five Indian states, West Bengal, Assam, Meghalaya, Tripura and Mizoram.

The Tropic of Cancer, at 23 degrees 30 minutes north, enters India in Gujarat and leaves it in Mizoram, passing on the way through Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram.

This meridian, which passes near Mirzapur in Uttar Pradesh, runs roughly through the middle of the country and was adopted as the standard meridian so that the whole of India could keep one time.

Indira Point lies at the southern end of Great Nicobar, the largest island of the Nicobar group, at about 6 degrees 45 minutes north, and is the southernmost point of the territory of India; it was known as Pygmalion Point before being renamed.

The correct answer is B, Kanyakumari, also called Cape Comorin, in Tamil Nadu, which stands at about 8 degrees 4 minutes north and is the southern tip of the Indian mainland, where the Arabian Sea, the Bay of Bengal and the Indian Ocean are said to meet.

Parallels of latitude are circles drawn parallel to the equator, and they grow shorter as one moves towards the poles, until a pole is a point with no length at all.

The correct answer is B, the Ten Degree Channel, which lies roughly along the parallel of ten degrees north and separates the Andaman group in the north from the Nicobar group in the south; Little Andaman lies to its north and Car Nicobar to its south.

The mainland of India extends from about 68 degrees 7 minutes east to about 97 degrees 25 minutes east, a longitudinal spread of roughly 29 degrees.

Carbon monoxide binds to haemoglobin far more strongly than oxygen does and forms carboxyhaemoglobin, so the blood cannot pick up oxygen even though breathing goes on; the gas is colourless and odourless, which makes it the more dangerous, and it is produced by the incomplete burning of fuel in closed…

Compressed natural gas is mainly methane, the simplest hydrocarbon, and biogas from a gobar gas plant is also mostly methane along with carbon dioxide, produced by the anaerobic decay of organic matter; methane is also called marsh gas because it bubbles up from waterlogged ground.

In the Haber process nitrogen from the air and hydrogen are combined under high pressure at a few hundred degrees Celsius over a catalyst of finely divided iron, and the ammonia so made is the starting point of nitrogenous fertilisers such as urea and of nitric acid.

Carbon dioxide reacts with lime water, a solution of calcium hydroxide, to form insoluble calcium carbonate, whose fine white particles make the liquid look milky; if more of the gas is passed the milkiness disappears as soluble calcium bicarbonate is formed, and that second step is often the harder half…

When an electric discharge is passed through neon at low pressure it glows a bright reddish orange, which is why the tubes of advertising signs and warning lights are filled with it, and the name neon sign has stuck to such tubes whatever gas they now contain.

Argon is chemically inert, so the hot tungsten filament does not react with it, and its presence also slows the evaporation of tungsten, which is why bulbs are filled with argon, sometimes mixed with nitrogen, instead of being left as a vacuum.

It is called laughing gas because it produces a feeling of elation when inhaled in small quantities, and it is used as a mild anaesthetic in dentistry and minor surgery and as the propellant in whipped cream; it is also a greenhouse gas.

Chlorine released from chlorofluorocarbons destroys ozone fastest where polar stratospheric clouds form in the extreme cold of winter, because those ice clouds hold the chlorine compounds that sunlight then breaks up; the thinning is therefore deepest over Antarctica, where it is called the ozone hole, and is seen over the…