UPSC GK Questions 2026

In a liquid the resistance to flow comes mainly from the attraction between neighbouring molecules. Heating gives the molecules energy to slip past one another, so the attraction matters less and the liquid thins; hot honey and warm engine oil pour far more easily than cold.

Evaporation is a surface phenomenon in which the fastest-moving molecules of a liquid break free. Doing so needs the latent heat of vaporisation, and that energy is drawn from the liquid left behind and from whatever the liquid touches, so both grow cooler.

This is the heat one gram of ice at 0 degrees Celsius must absorb to become one gram of water at 0 degrees Celsius; the temperature does not rise at all while it melts, because the energy goes into breaking the hydrogen-bonded lattice.

Bromine is a dark reddish-brown, dense, fuming liquid at ordinary room temperature, with a melting point of about minus 7 degrees Celsius and a boiling point of about 59 degrees Celsius.

Plasma is a hot, electrically conducting mixture of free electrons and positive ions produced when a gas is heated or strongly ionised.

Water contracts as it is cooled from higher temperatures like any other liquid, but only down to 4 degrees Celsius.

Boyle s law applies to a fixed mass of gas at constant temperature and states that pressure is inversely proportional to volume, so the product of the two is a constant: P1 into V1 equals P2 into V2.

In 1924 Satyendra Nath Bose sent Albert Einstein a paper deriving Planck s radiation law by counting indistinguishable light quanta.

A change of state is governed by the energy of the particles. When a solid absorbs heat its particles vibrate harder until the force holding them in the lattice is overcome and it melts; further heat lets the liquid particles escape as vapour.

Trained as a physicist, she turned to agriculture and founded Navdanya, a network of community seed banks that collects, stores and freely exchanges traditional varieties of rice, millet, pulses and oilseeds, and that campaigns against the patenting of seed and of plants long used in India.

The Tawa project on a tributary of the Narmada in Hoshangabad district of Madhya Pradesh brought canal irrigation to black cotton soil that already held water well.

From the late nineteen seventies Jadav Payeng planted saplings year after year on a bare, eroding sandbar of the Brahmaputra near Majuli, and the patch grew into a forest of several hundred hectares that is now called the Molai forest after him.

In 1982 the government proposed to convert the natural sal forests of Singhbhum, then in Bihar and now in Jharkhand, into plantations of teak, which fetches a far higher price as timber.

He carried the Chipko message on foot across the Himalaya and summed up its argument in the phrase that ecology is permanent economy, meaning that a standing forest yields soil, water and pure air for ever while felled timber yields money once.

Through the Tarun Bharat Sangh he revived the johad, the traditional crescent-shaped earthen check dam, across the dry Alwar district of Rajasthan.

At Khejarli near Jodhpur in 1730, the men of the Maharaja of Jodhpur came to fell khejri trees for lime kilns needed to build a new palace.

The Kerala State Electricity Board proposed a hydroelectric dam across the Kunthipuzha river in Palakkad district, which would have submerged a tract of undisturbed tropical evergreen rainforest and the habitat of the lion-tailed macaque.

She has led the Narmada Bachao Andolan since it took shape in 1985 against the Sardar Sarovar and other large dams on the Narmada, arguing that the displaced, many of them tribal, were never given land or proper rehabilitation.

The Appiko movement began in 1983 at Salkani village in the Sirsi taluk of Uttara Kannada district, in the Western Ghats of Karnataka, under Pandurang Hegde.

The movement began in 1973 at Mandal village in Chamoli district of the Garhwal Himalaya, then part of Uttar Pradesh and today in Uttarakhand.