RRB Group D GK Questions 2026

The potential difference between two points in a circuit is defined as the work done in moving a unit positive charge from one point to the other.

By Ohm's law, at a constant temperature the current through a conductor is directly proportional to the potential difference across its ends, since the current equals the potential difference divided by the resistance.

Set up in 1981 and based at Dehradun, it assesses the country's forest and tree cover from satellite data and brings out the India State of Forest Report once every two years, giving the cover state by state and by density class.

The Montreal Protocol was adopted under the Vienna Convention of 1985 and sets a timetable for phasing out chlorofluorocarbons, halons and similar chemicals.

The convention was signed in 1971 at Ramsar, a town in Iran, and is the oldest of the modern global conservation treaties.

It added Article 48A to the directive principles, asking the state to protect and improve the environment and to safeguard forests and wildlife, and Article 51A, clause g, to the fundamental duties, laying the same obligation on every citizen.

The Authority was set up under the Biological Diversity Act of 2002 and is based at Chennai in Tamil Nadu.

The Board was created by that Act to advise the central government, to lay down standards for effluents and to coordinate the work of the State Pollution Control Boards, which were set up by the same law in the states.

The National Green Tribunal Act was passed in 2010 and the tribunal began work in the same year, to provide quick and specialised disposal of cases on environmental protection and forest conservation.

The Act was passed in the wake of the Bhopal gas tragedy and gives the central government a general power to take any measure it considers necessary to protect and improve the quality of the environment.

The National Clean Air Programme was launched by the Ministry of Environment, Forest and Climate Change in January 2019 as a national framework to cut particulate pollution in cities that do not meet the national ambient air quality standards.

The Stockholm Convention was adopted in 2001 and came into force in 2004.

Founded in 1948 and based in Switzerland, it maintains the Red List of Threatened Species, which grades species as least concern, near threatened, vulnerable, endangered, critically endangered, extinct in the wild or extinct.

On the night of 2 and 3 December 1984, methyl isocyanate gas leaked from the pesticide plant of Union Carbide India Limited at Bhopal in Madhya Pradesh, killing thousands of people and injuring many more.

A tunnel diode, also called an Esaki diode after Leo Esaki who made it in 1957, is heavily doped on both sides, so its depletion layer is extremely thin and electrons cross it by quantum tunnelling.

Newton's universal law of gravitation states that every two bodies attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them, written F = GMm/d².

Aerobic respiration is the breakdown of glucose in the presence of oxygen, giving carbon dioxide, water and a large amount of energy.

Nuclear power is produced by the fission of uranium and thorium, which are mined ores present in fixed quantities in the Earth's crust, so once used they cannot be replaced within human time.

Potassium sits in group 1 of the periodic table along with lithium, sodium, rubidium, caesium and francium, and these six are called the alkali metals because their oxides and hydroxides dissolve in water to give strong alkalis.

Graphite is built of flat sheets of carbon atoms arranged in hexagons, and while the atoms inside a sheet are joined by strong covalent bonds, the sheets themselves are held to one another only by weak van der Waals forces.