SSC CGL GK Questions 2026

A Geiger-Muller counter contains a gas-filled tube in which an entering ray ionises the gas and sets off a pulse of current, so each pulse counts one particle; a film badge worn by a worker records the total dose instead.

Iodine-131 has a half-life of roughly eight days, which is why the danger from it after an accident is intense but short-lived, and why potassium iodide tablets are distributed at once so that the thyroid gland is saturated with ordinary iodine and absorbs less of the radioactive form.

Reactor number four of the Chernobyl plant, in Ukraine in the then Soviet Union, exploded on 26 April 1986 and scattered radioactive iodine, caesium and strontium over a wide area of Europe.

The becquerel, symbol Bq, is the SI unit of activity and equals one disintegration per second.

Strontium lies just below calcium in the same group of the periodic table and behaves chemically like it, so strontium-90 taken in through milk, water or food is deposited in bone and in teeth in place of calcium.

A cooling tower releases the heat of used cooling water to the atmosphere by evaporation or by air flow, so that the water leaving the plant is close to the temperature of the receiving river or lake.

Thermal and nuclear power stations draw large volumes of water to condense steam and return it several degrees warmer, which makes them the single largest source of waste heat in rivers, lakes and coastal waters.

The solubility of a gas in water decreases as the temperature of the water rises, so hot water discharged from a power station holds less dissolved oxygen.

The Rules define a silence zone as the area up to 100 metres around a hospital, an educational institution or a court, and such an area has to be declared by the competent authority.

The Rules of 2000 lay down 55 decibel as the day-time limit and 45 decibel as the night-time limit for a residential area.

The Noise Pollution (Regulation and Control) Rules were notified in the year 2000 and they were framed under the Environment (Protection) Act, 1986.

The decibel, written dB, is the unit in which the intensity level of sound is expressed, and it is named after Alexander Graham Bell.

Born on 12 January 1863 at Kolkata, he represented Hinduism at the Parliament of the World's Religions in Chicago in 1893 and founded the Ramakrishna Mission in 1897; his birthday has been observed as National Youth Day since 1985.

Born on 25 December 1924, he served three terms as Prime Minister, and the day is observed as Good Governance Day; his memorial in Delhi is named Sadaiv Atal.

Gandhi was assassinated on 30 January 1948 at Birla House in Delhi, and the day is observed every year as Martyrs' Day, with two minutes of silence at eleven in the morning.

Known as the champion of the peasantry, he served as Prime Minister and his memorial in Delhi is named Kisan Ghat; his birthday, 23 December 1902, is observed across the country as Kisan Diwas or Farmers' Day.

Born on 5 September 1888, he was a philosopher and teacher before becoming the first Vice President and the second President of India, and when his students wished to celebrate his birthday he asked that it be kept as Teachers' Day instead.

Chaitya Bhoomi, at Dadar on the sea front in Mumbai, is the place where Dr. B. R. Ambedkar was cremated after his death on 6 December 1956, and his followers gather there in lakhs on Mahaparinirvan Diwas.

Shakti Sthal, the place of power, is the samadhi of Indira Gandhi, who was assassinated on 31 October 1984, and Vir Bhumi, the land of the brave, is the samadhi of Rajiv Gandhi, who was assassinated on 21 May 1991, a day now observed as Anti-Terrorism Day.

Patel was born on 31 October 1875 and, as the first Deputy Prime Minister and Home Minister, brought the princely states into the Indian Union, which is why his birthday is observed as National Unity Day; the Statue of Unity at Kevadia in Gujarat, 182 metres high, was inaugurated on…