Railway GK Questions 2026

Red has the longest wavelength in visible light, about 700 nm, so the tiny particles of air, fog, smoke and dust scatter it the least.

The reactivity series lists metals from the most reactive to the least reactive, and potassium heads it because it loses its single outer electron most easily.

It gives the direction of the force, and so of the motion, on a current-carrying conductor placed in a magnetic field, which is exactly what turns the coil of a motor.

Combustion means burning in oxygen, and complete burning of methane gives carbon dioxide, water, heat and light. The equation is balanced: one carbon, four hydrogen and four oxygen atoms on each side.

The N shell is the fourth shell (n = 4), and the most electrons a shell can hold is given by the formula 2n², so 2 × 4² = 32.

In diamond every carbon atom is joined to four other carbon atoms by strong covalent bonds. These bonds point towards the corners of a tetrahedron and build a rigid three-dimensional network that runs through the whole crystal.

It is the standard set of rules used for reflection by spherical mirrors and for the mirror formula. Under this convention the pole of the mirror is the origin and the principal axis is the x-axis.

Nitrogen is an unreactive gas, so it drives the oxygen out of the packet and stops the oil in the chips from getting oxidised.

Violet has the shortest wavelength in visible light, so glass slows it the most and bends it the most. White light is a mix of seven colours, remembered as VIBGYOR.

Each metal here is paired with one of its best-known ores. Bauxite is hydrated aluminium oxide; alumina is refined from it and then broken down by electrolysis in the Hall-Héroult process.

The number 235 is the mass number and uranium's atomic number is 92, so the nucleus holds 235 minus 92, that is 143 neutrons.

Bihu is the chief festival and folk dance of Assam. The dance is performed by young men and women in groups to the beat of the dhol and the pepa, a pipe made of buffalo horn, with quick steps and graceful hand movements.

Pochampalli, also written Pochampally, is a weaving town in the Yadadri Bhuvanagiri district of Telangana, not far from Hyderabad. It is famous for ikat sarees, in which the threads are tied and dyed before weaving, so the pattern appears as the cloth is woven.

A johad is a small crescent-shaped earthen dam that villagers build together to catch and store rainwater. It is used mainly in Rajasthan and Haryana, where rain is scarce and falls in only a few months of the year.

The United Nations General Assembly named 5 June as World Environment Day in 1972, and the day has been observed every year since 1974.

Sulphur dioxide and nitric oxide are the gases behind acid rain. When coal, petrol and diesel are burnt in power plants, factories and vehicles, they release sulphur dioxide and oxides of nitrogen such as nitric oxide.

At great heights the air is thin, so the atmospheric pressure acting on the body is much lower than at sea level.

Bronze is made by melting copper and tin together, with copper as the main metal. It is harder than pure copper and does not corrode easily, so it has been used for statues, bells, medals and utensils for thousands of years.

All three are needed by plants only in very small amounts, which makes them micronutrients. Plants need macronutrients in large amounts: nitrogen, phosphorus and potassium as primary nutrients, and calcium, magnesium and sulphur as secondary ones.

Of the three, only citrus canker is caused by bacteria; rust of wheat is caused by a fungus and yellow vein mosaic of bhindi by a virus.