RRB Group D GK Questions 2026

Radiation carries heat as electromagnetic waves, so it needs no material medium and can travel through a vacuum. This is how the heat of the Sun crosses empty space to reach the Earth, and why you feel warmth in front of a fire without touching it.

Ethyl alcohol, or ethanol, dissolves resins, gums, dyes and oils and also evaporates quickly, so paints, varnishes and polishes made with it dry fast; this makes it the common solvent of the paint industry.

Iodine is the non-metal in the antiseptic painted on cuts and wounds, sold as tincture of iodine, which is a solution of iodine in alcohol.

All three are mixtures: wood is made of cellulose, lignin, water and resins, air is a mixture of nitrogen, oxygen and other gases, and sand is mostly silica mixed with mineral and shell grains.

Quick lime is calcium oxide, CaO, and not calcium carbonate, so it is the odd one out. Limestone, chalk and marble are all natural forms of calcium carbonate, CaCO3, differing only in how they were formed and in how hard they are.

Distilled water has had its dissolved salts removed, so it holds almost no free ions to carry charge and does not conduct electricity.

Time period is the time taken for one full oscillation, so it is the total time divided by the number of oscillations: 64 divided by 40 gives 1.6 seconds.

The LPG supplied in household cylinders is mainly a mixture of butane and propane, two gases that turn liquid under moderate pressure.

Only at -40 do the two scales read alike, so -40 °C and -40 °F are the very same temperature.

The Shivir was conducted in hybrid mode, anchored from the national capital and held physically at participating locations, and more than 3,800 urban local bodies, rural local bodies and line departments took part in it.

A senior official of this ministry gave out the attendance and service figures for the Shivir and named the states whose municipal corporations organised health camps, namely Meghalaya, Maharashtra, Uttar Pradesh, Telangana, Kerala and Bihar.

Every other option is a real figure from the same Shivir attached to the wrong service, which is exactly how such a question is set.

Concentration tells how much solute is present in a given amount of solution, and the three standard percentage forms are mass by mass, mass by volume and volume by volume; volume by mass is not one of them.

The Tyndall effect is the scattering of a beam of light by particles suspended in a medium, and it needs particles large enough to scatter that light.

Sulfur dioxide is made of one sulfur atom and two oxygen atoms, so its molecular mass is the sum of their atomic masses: 32 plus 2 multiplied by 16, that is 32 plus 32, which gives 64 u. Molecular mass is expressed in unified atomic mass units, written u, and…

Calcium chloride is an ionic compound, so it has a formula unit mass rather than a molecular mass, and the value is found by adding the atomic masses of all the atoms in the formula.

Bacteria in the mouth break down leftover food particles and produce acid, not base, so statement d is the incorrect one.

Litmus is a natural indicator obtained from lichens, which are a partnership between an alga and a fungus, and in a neutral solution it shows a purple colour.

A haloalkane carries a halogen atom - fluorine, chlorine, bromine or iodine - bonded to a carbon chain, so no oxygen appears in its functional group at all.

Cyclohexane is a closed ring of six carbon atoms joined by single bonds, and each carbon carries two hydrogen atoms, which gives C6H12.