NDA GK Questions 2026

Newton passed a narrow beam of sunlight through a glass prism in a darkened room and obtained a band of seven colours on the wall, which he named the spectrum.

By the sign convention the focal length of a concave lens is negative, so f is minus 15 centimetres, and the object distance measured against the direction of the incident light is minus 30 centimetres.

A denser medium has a higher refractive index, and the refractive index is the speed of light in vacuum divided by its speed in the medium, so light must travel more slowly inside it.

Distillation separates a liquid from a solution or from another liquid by boiling it and condensing the vapour, so it is used when the components differ in boiling point, as in getting pure water from salt water or separating acetone from water.

Among the allotropes of carbon, graphite has the lowest standard enthalpy of formation, which is taken as zero, so it is the reference state and the most stable form under ordinary conditions of temperature and pressure.

A conservative force is one whose work depends only on the starting and the finishing point, not on the path taken, and whose work around any closed path is zero.

Vyommitra is a half-humanoid robot built by the Indian Space Research Organisation and shown to the public in January 2020.

President Sukarno of Indonesia was the chief guest at India's first Republic Day on 26 January 1950, the day the Constitution came into force.

Prachi Choudhary finished third in that race, and her run was praised for earning India a place on the podium.

The pair won bronze in the squash mixed team event, and for Joshna the medal extended a remarkable run of consistency, since she has played at consecutive Asian Games and taken a medal at every edition since 2010.

Tajinderpal Singh won silver in the men's shot put with an impressive throw, and the Prime Minister noted that his focus and perseverance have brought India laurels over and over, so this medal is another milestone in a long career.

Prithvi II is test-fired from the Integrated Test Range at Chandipur on the Odisha coast, the DRDO range used for missile and rocket trials.

Sikkim does not touch Myanmar. Its neighbours across the border are Nepal to the west, China in the north and east, and Bhutan to the south-east.

Melting and boiling only have to break the weak forces between the molecules, not the strong bonds inside them, so little heat is needed.

The westerlies blow from the subtropical high pressure belt towards the subpolar low, which makes them south-westerly in the northern hemisphere and north-westerly in the southern.

Find each mass from F = ma, add the masses, then divide the same force by the total. The first block gives m1 = 5 ÷ 10 = 0.5 kg and the second gives m2 = 5 ÷ 20 = 0.25 kg.

Boron has three electrons in its outermost shell, so it is a trivalent element and is used as a p-type dopant.

A centre-tap full wave rectifier needs two p-n junction diodes, one for each half of the input cycle. The secondary winding of the transformer is tapped at its middle, so its two halves give equal voltages of opposite sign.

Kinetic energy depends on the square of the momentum, so the momentum grows as the square root of the energy.

A silicon diode in forward bias drops about 0.7 volt across itself, whatever the supply voltage is.