RRB NTPC GK Questions 2026

In glass, light of shorter wavelength travels more slowly, so the glass has a higher refractive index for it and bends it more.

A system whose walls let no heat pass in or out is called adiabatic, so any change in its state happens with zero heat exchange (Q = 0).

The Atal Innovation Mission (AIM) was set up by NITI Aayog in 2016 as the Government of India's flagship programme to promote innovation and entrepreneurship.

At the 2016 Rio de Janeiro Olympics, India won two medals, both by women: a silver in badminton and a bronze in wrestling.

Apart from the Sun, Proxima Centauri is the star nearest to the Earth, about 4.24 light years away. Proxima Centauri is a small, dim red dwarf in the constellation Centaurus and cannot be seen with the naked eye.

These are the only two elements that are liquid at standard room temperature and pressure: mercury is a metal and bromine is a non-metal.

Sodium carbonate, called washing soda in its hydrated form Na₂CO₃·10H₂O, removes both temporary and permanent hardness of water. Hard water contains dissolved calcium and magnesium salts, which stop soap from lathering.

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".