RRB Group D GK Questions 2026

Crude petroleum is a mixture of hydrocarbons with different boiling points, and fractional distillation separates them. In a refinery, crude oil is heated to about 400 °C and its vapour enters a tall fractionating column that is hot at the bottom and cooler towards the top.

Diagnostic laboratories spin blood samples in a centrifuge to separate the plasma or serum from the blood cells. In centrifugation a sample is rotated at high speed, so the denser particles are pushed to the bottom of the tube and the lighter liquid stays on top.

One pascal is defined as a force of one newton acting on an area of one square metre. Pressure is force per unit area, and its SI unit, named after the French scientist Blaise Pascal, is the pascal (Pa): 1 Pa = 1 N/m².

A floating body is stable only when its metacentre lies above its centre of gravity. When a floating body tilts slightly, its centre of buoyancy, the centre of the displaced liquid, shifts to one side.

Union Minister of Youth Affairs and Sports Dr Mansukh Mandaviya said that under this scheme, which the Union Cabinet approved, the government is deepening its collaboration with corporate partners, and that CSR backed partnerships of this kind will help build a truly national sports ecosystem.

The National Sports Development Fund was established by the Government of India in 1998 under this Act, and its purpose is to mobilise resources from individuals and corporate organisations for the development of sport in the country.

Indian boxers finished the Asian Games 2026 with six medals in total, three of them gold and the other three bronze, and this showing is the reason the new partnership is described as coming at an important time for the sport.

Under the memorandum of understanding signed with the National Sports Development Fund and the Sports Authority of India, Indian Oil Corporation will provide this amount over a period of two years from its corporate social responsibility funds.

A simple periscope has two plane mirrors facing each other in parallel, each tilted at 45° to the tube. Light from the object enters the top opening and strikes the upper mirror, which is set at 45° and turns the light through 90° down the tube.

This is false, because variations differ in how well they suit the environment, and that difference is the basis of natural selection.

Unsaturated hydrocarbons have a high carbon content and burn with a yellow, sooty flame, while saturated ones usually burn with a clean blue flame.

Milk of magnesia is a suspension of magnesium hydroxide, a mild base that neutralises excess stomach acid without harming the body.

Energy equals power multiplied by time: 0.1 kW × 30 hours = 3 kWh, which is 3 units. The bulb's power is 100 W, which is 0.1 kW.

Chromosomes are made of DNA wound around proteins, mainly histones; together this DNA-protein material is called chromatin. In eukaryotic cells, a very long DNA molecule wraps around groups of eight histone proteins to form beads called nucleosomes.

Chlorophyll is held in the chloroplasts, the green plastids of leaf cells where photosynthesis takes place. A chloroplast is a double-membrane organelle.

When a conductor moves in a magnetic field and a current is induced in it, this rule gives the direction of that induced current.

HIV infects and destroys helper T lymphocytes, the white blood cells that coordinate the body's immune response, so immunity steadily collapses.

Cancer is uncontrolled cell division that follows the loss of the checks that normally govern growth. Normal cells divide only when signalled and stop when they touch neighbouring cells, a property called contact inhibition.

Blue baby syndrome, or methaemoglobinaemia, strikes infants who drink water with excess nitrate, usually from fertiliser runoff or sewage. In an infant's digestive system, nitrate is converted into nitrite, which oxidises the iron of haemoglobin and turns it into methaemoglobin.

A kelvin and a degree Celsius are the same size, but the Kelvin scale starts at absolute zero, which is −273.15 °C. The kelvin is the SI unit of temperature.