Static general knowledge makes up about 90% of Part B of the NDA General Ability Test, about 360 of its 400 marks. The NDA & NA (II) 2026 notice divides it into five sections: Physics (about 25%), Chemistry (about 15%), General Science (about 10%), History, Freedom Movement etc. (about 20%) and Geography (about 20%). Half of Part B is science. Physics covers matter, motion, gravitation, heat, sound, light, magnetism, electricity and the working of everyday devices such as the siphon, pressure cooker, periscope and safety fuse. Chemistry covers changes of matter, elements and compounds, common gases, acids, bases and salts, carbon, fertilizers and the materials used to make soap, glass, cement and gunpowder. General Science covers cells, the human body, diseases, diet, the solar system and eminent scientists. Section D spans Indian history and culture, the freedom movement, the Constitution, Five Year Plans, Panchayati Raj and world history from the Renaissance to the Russian Revolution. Geography covers the Earth, rocks, oceans, the atmosphere and climate, and India's resources, industries, ports and trade. This page holds GK24's topic-wise GK notes for NDA, in English and Hindi, written as short facts and tables. Read a topic, then solve its quiz and previous-year questions on this site.
The flat-topped seamounts found on the ocean floor are called
A seamount is an isolated volcanic peak rising from the deep sea floor without reaching the surface; where such a peak once stood at sea level and had its top worn flat by waves before subsiding, it is called a guyot.
Read the full explanation →Which of the following water bodies records the highest salinity?
The correct answer is C, Lake Van in Turkey, which records a salinity of about 330 parts per thousand, the highest figure given in standard textbooks.
Read the full explanation →What is the average salinity of ocean water and which salt contributes the largest share of it?
Salinity is expressed in parts per thousand, so 35 ppt means 35 grams of dissolved salt in a kilogram of sea water.
Read the full explanation →The highest tidal range in the world is recorded at
The correct answer is B, the Bay of Fundy, between Nova Scotia and New Brunswick in Canada, where the funnel shape of the bay and the length of the inlet make the incoming tide pile up to a range of the order of fifteen to sixteen metres.
Read the full explanation →Spring tides occur on which days of the lunar month?
On these days the sun, the moon and the earth lie in a straight line, a position called syzygy, so the pulls of the sun and the moon act together and the tidal range is at its greatest; spring tides therefore occur twice in a lunar month and have nothing…
Read the full explanation →Which division of the ocean floor is the most important economically, holding the richest fishing grounds and most offshore petroleum?
It is the gently sloping, shallow margin of the continent, extending to a depth of about 200 metres with a gradient of one degree or less and an average width of about seventy to eighty kilometres, and it makes up roughly 7.5 per cent of the ocean area.
Read the full explanation →The deepest point of the earth's surface, the Challenger Deep, lies in which ocean trench?
The correct answer is B, the Mariana Trench, in the western Pacific Ocean, whose Challenger Deep reaches a depth of about eleven kilometres and is the deepest known point on the earth's surface.
Read the full explanation →With reference to the latitudinal distribution of salinity in the oceans, which of the following statements is correct?
I. The highest salinity is recorded in the equatorial regions.
II. The salinity of the oceans of the Northern Hemisphere is higher than that of the Southern Hemisphere.
Statement I is wrong because the equatorial belt receives very heavy rainfall and has high cloud cover, so the surface water there is diluted; the highest salinity in the open ocean is recorded in the subtropical high pressure belts, roughly between twenty and thirty degrees of latitude, where skies are…
Read the full explanation →A piece of ice floating in a glass of water melts completely. What happens to the level of the water in the glass?
While the ice floats it displaces a volume of water whose weight equals the weight of the ice, by the law of flotation.
Read the full explanation →The viscosity of a liquid and the viscosity of a gas behave in which way when the temperature is raised?
In a liquid, viscosity comes chiefly from cohesion between molecules; heating weakens that cohesion, so the layers slide past one another more easily and the viscosity falls, which is why engine oil becomes thinner as the engine warms and why honey flows freely when it is warmed.
Read the full explanation →The spherical shape of a small liquid drop is due to
Cohesive forces pull the molecules at the surface of a liquid inward, so the surface behaves like a stretched membrane and takes the smallest area that can enclose the given volume; for a fixed volume the shape of least surface area is a sphere, which is why a free drop…
Read the full explanation →Which of the following is the SI unit of the coefficient of viscosity?
The correct answer is B, pascal second, equal to a newton second per square metre, which follows from Newton's law of viscosity, where the shearing stress in pascals is divided by the velocity gradient in reciprocal seconds.
Read the full explanation →Pascal's law is the principle behind which of the following devices?
Pascal's law says that pressure applied to an enclosed fluid is transmitted undiminished to every part of the fluid and to the walls of the vessel, so a modest push on the brake pedal creates a pressure in the brake fluid that is passed to the wider pistons at every…
Read the full explanation →A liquid rises upto a height greater than that for water in given capillary tube. Its reason may be that
In a capillary tube the height of rise is directly proportional to the surface tension of the liquid and inversely proportional to its density and the radius of the tube.
Read the full explanation →A fluid in which resistance to deformation is independent of the shear stress, is known as
In such a fluid the shearing stress is directly proportional to the rate of shear, so the coefficient of viscosity, which measures the resistance to deformation, keeps the same value whatever the stress applied; water, air, petrol and thin oils behave in this way.
Read the full explanation →Centre of buoyancy is
The upthrust on a body is the resultant of the pressure forces of the fluid around it, and that resultant acts through the centre of gravity of the fluid the body has pushed aside, which is why the point is called the centre of buoyancy.
Read the full explanation →What percent of the total volume of an iceberg floats above the water surface? Assume the density of ice to be 920 kg/m3 and the density of water to be 1000 kg/m3.
A floating body displaces its own weight of fluid, so the fraction of its volume that lies below the surface equals the ratio of its density to the density of the fluid, here 920 divided by 1000, which is 0.92.
Read the full explanation →On which of the following factors does the magnitude of the buoyant force acting on a body in a given fluid depend?
By Archimedes' principle the upthrust on a body equals the weight of the fluid it displaces, and that weight is the volume of the body actually immersed multiplied by the density of the fluid and by the acceleration due to gravity.
Read the full explanation →The 2026 climb was which joint mountaineering expedition of the Indian and Argentine armies?
The two armies first climbed together on Mt Aconcagua at 6,962 metres in Mendoza, Argentina, in January 2025, then on Mt Kun at 7,077 metres in the Suru valley of Ladakh in August 2025, and the Uttarakhand outing of this year was therefore the third in the series.
Read the full explanation →Who led the Joint Indo-Argentine Army Mountaineering Expedition of 2026?
He headed the party of 35 climbers, of whom 25 belonged to the Indian Army and 10 to the Argentine Army, and the group was flagged off from the Manekshaw Centre in New Delhi on 21 August 2026.
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