UPSC CAPF GK Questions 2026

Plants need magnesium in fairly large amounts, so it is a macronutrient, not a micronutrient. Plant nutrients are grouped by how much of them a plant needs.

S-waves are transverse waves: they shake the ground at right angles to their direction of travel, and that sideways motion forms crests and troughs.

The events fall in 1972, 1974, 1985 and 2001 in that order, which is also UPSC's official key. The Simla Agreement was signed on 2 July 1972 by Indira Gandhi and Zulfikar Ali Bhutto after the 1971 war; it turned the ceasefire line in Kashmir into the Line of Control.

Lactase breaks down lactose, the sugar in milk, so a person who still makes enough of it can digest milk at any age.

For a 4d orbital, n = 4 and l = 2, which gives l = 2 angular nodes and n − l − 1 = 1 radial node.

A bacterium is a living cell filled with cytoplasm, while a virus is only genetic material inside a protein coat.

Accelerators speed up the vulcanisation of rubber; they are not a part of paint.

Animal cells are bounded only by a flexible cell membrane; a rigid cell wall is found in plants, fungi and bacteria.

The first three are written into Article I of the SAARC Charter; ending cross-border terrorism is not one of its listed objectives.

The number after PM gives the upper size limit of the particles in micrometres. Particulate matter is classed by aerodynamic diameter: PM10 is 10 micrometres or less, PM2.5 is 2.5 micrometres or less, and PM1 is 1 micrometre or less, about one-seventieth of a human hair's width.

A liquid boils when its vapour pressure equals the pressure above it, so less outside pressure means boiling starts at a lower temperature.

All three subjects sit in the list named against them in the Seventh Schedule. The Seventh Schedule, read with Article 246, divides law-making powers into three lists.

Magnesium burns in air with a dazzling white flame, which is why it goes into fireworks, sparklers and flares. When magnesium ribbon is heated it reacts with oxygen to form white magnesium oxide (2Mg + O2 → 2MgO), giving out intense heat and brilliant white light, including ultraviolet.

A short-sighted (myopic) person sees near things clearly but distant things blurred, and a concave lens corrects it.

A compound microscope uses two convex lenses, and its magnification depends on the tube length. The objective is a convex lens of very short focal length that forms a real, enlarged image of the specimen.

The third law does not make one force the cause and the other the effect; action and reaction arise together, at the same instant.

A real, inverted image of the same size forms only when the object sits at twice the focal length of a convex lens, so 2f = 10 cm and f = 5 cm.

Sunlight reaching a glasshouse is mostly visible light and short-wavelength (near) infrared, which glass transmits easily. The plants and soil inside absorb it, warm up and re-radiate the energy as long-wavelength infrared, because cooler bodies emit at longer wavelengths.

Plantations do lie mostly in the humid tropics, but the soils there are generally poor, not highly fertile. Plantation farming grows a single cash crop such as tea, coffee, rubber, sugarcane, cocoa, banana or oil palm on large estates with heavy capital and hired labour.

Light inside the fibre strikes the boundary at more than the critical angle, so it is reflected back again and again instead of escaping.