Railway GK Questions 2026

Abhinav Bindra won the men's 10 m air rifle event at the 2008 Beijing Olympics on 11 August 2008, India's first individual Olympic gold.

H₂S is a colourless gas with the familiar smell of rotten eggs, and the human nose can detect it even in very small amounts.

Nylon 6 is made from a single monomer, caprolactam, whose ring opens on heating and joins up into long polyamide chains.

The Swedish chemist Berzelius proposed around 1813–1814 that each element be written with one or two letters taken from its name, the system still used today.

A soda-acid extinguisher holds a solution of sodium hydrogen carbonate (baking soda) and a small bottle of sulphuric acid; when the two mix, carbon dioxide is released.

Nitrogen gas is the element itself in a very stable form, and plants cannot take it up directly from the soil or the air, so it is not used as a fertilizer.

Lactobacillus turns the lactose sugar of milk into lactic acid, which sours the milk and makes it set into curd.

The lander of Chandrayaan-2 was named Vikram after Vikram Sarabhai, the father of India's space programme. Chandrayaan-2 was launched by ISRO on 22 July 2019 on a GSLV Mk III rocket from Sriharikota.

On heating, sodium bicarbonate releases carbon dioxide gas, whose bubbles make dough rise and turn cakes and bread soft and spongy.

The speed of sound in air increases, not decreases, as temperature rises, so statement B is the incorrect one. Sound in a gas travels faster when the gas is warmer, because its molecules move faster and pass the vibration on more quickly.

The bulb's resistance stays the same, and since power varies as the square of voltage, halving the voltage cuts the power to one-fourth.

Strain is a ratio of two lengths (or two volumes), so its units cancel and it has no dimensions. When a force deforms a body, strain measures the fractional change in its shape or size.

Probiotics are live, helpful microbes taken in food or supplements to improve the balance of bacteria in the gut. The word means "for life", the opposite of antibiotic, "against life".

A positive power means a converging (convex) lens, and f = 1/P = 1/2 = 0.5 m. The power of a lens is the reciprocal of its focal length in metres: P = 1/f. Its SI unit is the dioptre (D), and 1 D is the power of a lens…

Using kinetic energy = ½mv² with the mass in kilograms gives a speed of exactly 10 m/s. First convert the mass to SI units: 2000 g = 2 kg.

SONAR sends out ultrasonic pulses and times their echo from underwater objects. SONAR stands for Sound Navigation and Ranging.

This follows from Newton's third law and his law of gravitation. Newton's law of gravitation gives the force between two bodies as F = Gm₁m₂/r².

Resistivity is a property of the material itself, so changing the length of a copper wire does not change it.

. A Fischer projection draws a molecule as a cross: the horizontal bonds point towards the viewer and the vertical bonds point away.

Ammonium chloride sublimes: on heating, it changes directly from a solid into vapour without melting, and the vapour turns back into solid on a cool surface.