Defence GK Questions 2026

Ammonium sulphide is an unstable, foul-smelling compound that breaks down to release ammonia and toxic hydrogen sulphide, so it is not used as a fertiliser.

For an astronomical telescope in normal adjustment the magnifying power equals the focal length of the objective divided by that of the eyepiece, so the eyepiece focal length is 50 ÷ 25 = 2 cm.

Barley is sown in the cool, dry season after the monsoon and harvested in spring, which makes it a rabi crop in the northern states.

Vegetables and fruits supply most of the vitamins and minerals in a vegetarian diet, which is why they are called protective foods.

Silver bromide is the light-sensitive compound coated on black and white photographic film and paper, because light breaks it down into tiny grains of silver metal.

Speed tells only how fast a body moves, while velocity also tells the direction of motion, and a quantity with both magnitude and direction is a vector.

A hypertonic solution has a higher solute concentration than the cell sap, so water leaves the cells by osmosis and the protoplast shrinks away from the cell wall.

The Central Institute of Buddhist Studies is at Choglamsar near Leh in Ladakh. It is a deemed university funded by the Union Ministry of Culture.

Magnesium oxide melts at about 2,850 °C, far higher than the other three, because its small Mg2+ and O2− ions carry double charges and hold each other with a very strong ionic lattice.

That is false: black soils are among the most clayey soils of India, and their high clay content is what lets them swell when wet and crack when dry.

Bokaro in Jharkhand was set up in 1964 with Soviet (Russian) help, takes its iron ore from the Rourkela region and draws water and hydel power from the Damodar Valley Corporation.

That is false: in a physical change the molecules stay the same, and only their arrangement, state or shape alters.

Earthquake waves are of two basic types, body waves and surface waves, and surface waves are produced when body waves reach the surface and interact with the surface rocks.

Cardiac muscle is a muscular tissue, not a connective tissue; it is the striated, branched, involuntary muscle that makes up the wall of the heart and contracts rhythmically for life.

Genuine currency notes carry security features printed with fluorescent inks that glow only under ultraviolet light, so a UV lamp quickly exposes a fake.

When magnesium burns, magnesium loses electrons and is oxidised, while oxygen gains them and is reduced, so oxidation and reduction happen together.

A light year is the distance that light travels through a vacuum in one year, so despite the word year it measures length, not time.

Mica is a non-metallic mineral, a silicate that splits into thin, clear, flexible sheets, and no metal is extracted from it.

The Arthashastra is a manual on how a king should govern, defend and expand his state, so its main subject is statecraft.

A freely pivoted magnetic needle turns to line up with any magnetic field around it, so its deflection shows that a field is present and which way it points.