NDA GK Questions 2026

Mercury in water causes Minamata disease, and excess nitrate causes blue baby syndrome.

Sudan, often called North Sudan after South Sudan separated in 2011, has no coast on the Mediterranean Sea. Sudan lies south of Egypt in north-east Africa.

Wool is an animal fibre made mainly of the protein keratin. Polymers are giant molecules built from many small repeating units called monomers.

The horizontal distance from one crest to the next, or from one trough to the next, is the wavelength. Ocean waves are mostly made by wind blowing over the sea surface.

Sucralose is made from ordinary table sugar, sucrose, by changing its molecule. In making sucralose, three hydroxyl (OH) groups of the sucrose molecule are replaced by chlorine atoms.

Arjan Singh led the Indian Air Force during the 1965 war and was raised to the five star rank of Marshal of the Indian Air Force in 2002, the only officer of the Air Force ever to hold it.

Army Day marks the day in 1949 when Lieutenant General K. M. Cariappa took over as the first Indian Commander in Chief of the Indian Army from the last British holder of the post.

The Indian Naval Academy stands on the coast at Ezhimala in Kannur district of Kerala and is the basic training establishment for officer cadets of the Indian Navy and the Indian Coast Guard.

The motto is taken from the Bhagavad Gita and is translated as touch the sky with glory.

The Garhwal Rifles has its regimental centre at Lansdowne, a cantonment town in Pauri Garhwal district of Uttarakhand, and the regiment carries the motto Yudhaya Krit Nishchay.

The Madras Regiment traces its raising to 1758 and is accepted as the senior most and oldest infantry regiment of the Indian Army.

In the common ladder of the three services the Army Brigadier, the Navy Commodore and the Air Force Air Commodore occupy the same step.

The three services keep parallel ladders so that officers of equal standing can work together. At that level the Army has a Colonel, the Navy a Captain and the Air Force a Group Captain.

Article 53 of the Constitution vests the supreme command of the defence forces of the Union in the President, to be exercised in accordance with law.

Field Marshal is the five star rank of the Indian Army and stands above every other rank. It is ceremonial and is conferred only as a rare honour, and the officer who holds it never retires but remains on the active list of the Army for life.

Salinity is the quantity of dissolved salts in a kilogram of sea water, expressed in parts per thousand, and isohalines map its distribution; the open ocean averages about 35 parts per thousand, while enclosed seas with high evaporation such as the Red Sea are far saltier and seas fed by…

The earth's orbit is an ellipse, so its distance from the sun changes through the year; at perihelion, about 3 January, the earth is nearest the sun, which is why the northern winter half of the year is slightly shorter than the summer half.

A contour, whose technical name is isohypse, joins all points standing at the same height above sea level and is the chief means of showing relief on a topographical sheet; contours drawn close together mean a steep slope, contours far apart a gentle slope, and contours that merge indicate a…

In Alfred Weber's least-cost theory of industrial location, isodapanes are drawn through all points at which the total transport cost, for assembling the raw materials and for distributing the finished product, is the same; the innermost isodapane marks the area of least total cost, where the plant should be sited.

The Isthmus of Panama joins North and South America and separates the Caribbean Sea from the Pacific, and the Isthmus of Suez joins Africa to Asia; both have been cut by canals precisely because they are narrow.