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Type: Prelims Only

  • Modern Indian History-Events and Personalities

    History: Visva-Bharati University

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Visva-Bharati University

    Mains level: Nationalist education during freedom struggle

    The Visva-Bharati University established by Gurudev Rabindranath Tagore has completed its centenary.

    Do you remember the scheme of education by Gandhi Ji, called Nai Talim?

    Visva-Bharati University

    • The university was set up by Nobel laureate Rabindranath Tagore in 1921 at Santiniketan, Bolpur in West Bengal’s Birbhum district.
    • It was founded by Rabindranath Tagore who called it Visva-Bharati, which means the communion of the world with India.
    • Until independence, it was a college. Soon after independence, the institution was given the status of a central university in 1951 by an act of the Parliament.

    Its establishment

    • The origins of the institution date back to 1863 when Debendranath Tagore was given a tract of land by the zamindar of Raipur, the zamindar of Kirnahar.
    • He set up an ashram at the spot that has now come to be called chatim tala at the heart of the town.
    • The ashram was initially called Brahmacharya Ashram, which was later renamed Brahmacharya Vidyalaya.
    • It was established with a view to encouraging people from all walks of life to come to the spot and meditate.
    • In 1901 his youngest son Rabindranath Tagore established a co-educational school inside the premises of the ashram.

    What makes it special?

    • Rabindranath Tagore believed in open-air education and had reservations about any teaching done within four walls.
    • This was due to his belief that walls represent the conditioning of the mind.
    • Tagore did not have a good opinion about the Western method of education introduced by the British in India; on this subject, Tagore and Gandhiji’s opinion matched.
    • So he devised a new system of learning in Visva-Bharati. He allowed students to continue their course till the student and his teacher both are satisfied.
    • At Visva-Bharati, if a course demanded by a student is not available, then the university will design a course and bring teachers for that course.
    • The university would not be bothered by the consideration of whether there is a demand for the course.
  • Roads, Highways, Cargo, Air-Cargo and Logistics infrastructure – Bharatmala, LEEP, SetuBharatam, etc.

    What are Fastags?

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Fastag

    Mains level: RFID technology

    From January 1, all lanes of National Highways will accept only electronic payments through FASTag.

    Fastags work on a unique technology called RFID (Radio Frequency Identification). This has gone unnoticed in several competitive exams. Hence it is still relevant for the aspirants.

    Also read

    Fastags

    • As per Central Motor Vehicles Rules, 1989, since 1st December 2017, the FASTag had been made mandatory for all registered new four-wheelers and is being supplied by the Vehicle Manufacturer or their dealers.
    • It has been mandated that the renewal of fitness certificate will be done only after the fitment of FASTag.
    • For National Permit Vehicles, the fitment of FASTag was mandated since 1st October 2019.

    What is ‘FASTag’?

    • FASTags are stickers that are affixed to the windscreen of vehicles and use Radio Frequency Identification (RFID) technology to enable digital, contactless payment of tolls without having to stop at toll gates.
    • The tags are linked to bank accounts and other payment methods.
    • As a car crosses a toll plaza, the amount is automatically deducted, and a notification is sent to the registered mobile phone number.

    How does it work?

    • The device employs Radio Frequency Identification (RFID) technology for payments directly from the prepaid or savings account linked to it.
    • It is affixed on the windscreen, so the vehicle can drive through plazas without stopping.
    • RFID technology is similar to that used in transport access-control systems, like Metro smart card.
    • If the tag is linked to a prepaid account like a wallet or a debit/credit card, then owners need to recharge/top up the tag.
    • If it is linked to a savings account, then money will get deducted automatically after the balance goes below a pre-defined threshold.
    • Once a vehicle crosses the toll, the owner will get an SMS alert on the deduction. In that, it is like a prepaid e-wallet.
  • Wetland Conservation

    [pib] Tso Kar Wetland Complex

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Tso Kar Wetland Complex

    Mains level: Ramsar wetlands in India

    India has added Tso Kar Wetland Complex in Ladakh as its 42nd Ramsar site, which is a second one in the Union Territory (UT) of Ladakh. With this, India now has forty-two Ramsar sites.

    Try this PYQ:

    In which one among the following categories of protected areas in India are local people not allowed to collect and use the biomass?

    (a) Biosphere reserves

    (b) National parks

    (c) Wetlands declared under Ramsar convention

    (d) Wildlife sanctuaries

    Tso Kar Wetland Complex

    • It is a high-altitude wetland complex, consisting of two principal waterbodies, Startsapuk Tso, a freshwater lake of about 438 hectares to the south, and Tso Kar itself, a hypersaline lake of 1800 hectares to the north.
    • It is situated in the Changthang region of Ladakh.
    • It is called Tso Kar, meaning white lake, because of the white salt efflorescence found on the margins due to the evaporation of highly saline water.

    Ecological significance

    • Wetlands provide a wide range of important resources and ecosystem services such as food, water, fibre, groundwater recharge, water purification, flood moderation, erosion control and climate regulation.
    • They are, in fact, a major source of water and our main supply of freshwater comes from an array of wetlands which help soak rainfall and recharge groundwater.
    • The Tso Kar Basin is an A1 Category Important Bird Area (IBA) as per BirdLife International and a key staging site in the Central Asian Flyway.
    • The site is also one of the most important breeding areas of the Black-necked Crane (Grus nigricollis) in India.

    Back2Basics: Wetlands

    • A wetland is a distinct ecosystem that is flooded by water, either permanently or seasonally, where oxygen-free processes prevail.
    • The primary factor that distinguishes wetlands from other landforms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil.
    • Wetlands provide a wide range of important resources and ecosystem services such as food, water, fibre, groundwater recharge, water purification, flood moderation, erosion control and climate regulation.

    What is the Ramsar Convention?

    • The Ramsar Convention on Wetlands of International Importance Especially as Waterfowl Habitat is a treaty for the conservation and sustainable use of such sites.
    • The convention, signed in 1971 in the Iranian city of Ramsar, is one of the oldest inter-governmental accords for preserving the ecological character of wetlands.
    • Also known as the Convention on Wetlands, it aims to develop a global network of wetlands for the conservation of biological diversity and for sustaining human life.
    • Over 170 countries are party to the Ramsar Convention and over 2,000 designated sites covering over 20 crore hectares have been recognised under it.
  • Wetland Conservation

    Mapping: Caspian Sea

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Caspian Sea

    Mains level: Ecocides and their impact

    The Caspian is actually a lake, the largest in the world and it is experiencing a devastating decline in its water level that is about to accelerate.

    Note the countries bordering the Caspian Sea: Kazakhstan, Russia, Azerbaijan, Iran and Turkmenistan. Or else remember the acronym ‘TARIK(h)’ (Hindi word for date).

    You can frame a mnemonic statement of your choice. Do similarly for major lakes and inland seas. But dont let it move over TARIK pe TARIK!

    Caspian Sea

    • The Caspian Sea is the world’s largest inland body of water, variously classed as the world’s largest lake or a full-fledged sea.
    • As an endorheic basin, it lies between Europe and Asia.
    • An endorheic basin is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but converges instead into lakes or swamps, permanent or seasonal that equilibrates through evaporation
    • Its level is the product of how much water is flowing in from rivers, mostly the mighty Volga to the north, how much it rains and how much evaporates away.
    • At the end of the century, the Volga and other northern rivers will still be there.
    • However, a projected temperature rise of about 3℃ to 4℃ in the region will drive evaporation through the roof.

    Now try this PYQ:

    Q.Which of the following has/have shrunk immensely/ dried up in the recent past due to human activities?

    1. Aral Sea
    2. Black Sea
    3. Lake Baikal

    Select the correct option using the code given below:

    (a) 1 only

    (b) 2 and 3 only

    (c) 2 only

    (d) 1 and 3 only

    Why in news?

    • By the end of the century, the Caspian Sea will be nine metres to 18 metres lower. That’s a depth considerably taller than most houses.
    • The Caspian’s surface is already dropping by 7 cm every year, a trend likely to increase.
    • It means the lake will lose at least 25 per cent of its former size, uncovering 93,000 sq km of dry land.
    • If that new land were a country, it would be the size of Portugal.

    Past strides in its level

    • The Caspian Sea has a history of violent rises and falls.
    • In Derbent, on the Caucasus coast of Russia, submerged ancient city walls testify to how low the sea was in medieval times.
    • Around 10,000 years ago, the Caspian was about 100 metres lower.
    • A few thousand years before that it was about 50 metres higher than today and even over spilt into the Black Sea.
  • Modern Indian History-Events and Personalities

    Significance and History of National Farmers’ Day

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: National Farmers’ Day

    Mains level: Not Much

    National Farmers’ Day, or Kisan Diwas, is celebrated across the country on December 23 to honour India’s farmers.

    Do you think that the extraordinary haste with which the farm bills were pushed through both the Houses has created the present crisis?

    National Farmers’ Day

    • It marks the birth anniversary of the nation’s fifth PM Choudhary Charan Singh.
    • In 2001, the government decided to recognise Choudhary Charan Singh’s contribution to the agriculture sector and welfare of farmers by celebrating his birth anniversary as Kisan Diwas.
    • Since then, December 23 has been observed as National Farmers’ Day.
    • Generally, awareness campaigns and drives are organised across the country to educate people on the role of farmers and their contribution to the economy.

    Who was CCS and what was his connection with farmers?

    • Chaudhary Charan Singh, who briefly served as PM between 1979 and 1980, is widely regarded as one of the country’s most famous peasant leaders.
    • He was known for his pioneering work to promote the welfare of farmers and the agricultural sector.
    • Charan Singh was no stranger to the struggles faced by the Indian farmer. He was born into a middle-class peasant family in Uttar Pradesh on December 23, 1902.
    • Greatly influenced by the teachings of Mahatma Gandhi, he took an active part in the fight for independence.
    • After that, his political career largely focused on socialism in rural India.

    Major legislations

    • He was behind several major farmer-forward Bills, including the Land Utilization Bill of 1939 and the Debt Redemption Bill in 1939.
    • While serving as agriculture minister in 1952, he led UP in its efforts to abolish the Zamindari system.
    • In fact, he went on to draft the UP Zamindari and Land Reforms Bill himself.
    • On 23 December 1978, he founded the Kisan Trust — a non-political, non-profit making body — with the aim of educating India’s rural masses against injustice, and fostering solidarity among them.
  • Innovations in Sciences, IT, Computers, Robotics and Nanotechnology

    Why the universe has less ‘antimatter’ than matter?

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Matter, Anti-matter

    Mains level: Formation of the universe and the Big Bang

    This newscard is an excerpt from the original article published in DownToEarth.

    Try this PYQ:

    Q.The known forces of nature can be divided into four classes, viz, gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?

    (a) Gravity is the strongest of the four

    (b) Electromagnetism act only on particles with an electric charge

    (c) Weak nuclear force causes radioactivity

    (d) Strong nuclear force holds protons and neutrons inside the nuclear of an atom.

    What is Antimatter?

    • Antimatter is the opposite of normal matter. More specifically, the sub-atomic particles of antimatter have properties opposite those of normal matter.
    • The electrical charge of those particles is reversed.
    • Antimatter was created along with matter after the Big Bang, but antimatter is rare in today’s universe.
    • To better understand antimatter, one needs to know more about the matter.
    • The matter is made up of atoms, which are the basic units of chemical elements such as hydrogen, helium or oxygen.

    Their existence

    • The existence of antimatter was predicted by physicist Paul Dirac’s equation describing the motion of electrons in 1928.
    • At first, it was not clear if this was just a mathematical quirk or a description of a real particle.
    • But in 1932 Carl Anderson discovered an antimatter partner to the electron — the positron — while studying cosmic rays that rain down on Earth from space.
    • Over the next few decades’ physicists found that all matter particles have antimatter partners.
    • Scientists believe that in the very hot and dense state shortly after the Big Bang, there must have been processes that gave preference to matter over antimatter.
    • This created a small surplus of matter, and as the universe cooled, all the antimatter was destroyed, or annihilated, by an equal amount of matter, leaving a tiny surplus of matter.
    • And it is this surplus that makes up everything we see in the universe today.

    Studying the difference between matter and antimatter

    • A Quark is a type of elementary particle and a fundamental constituent of matter.
    • Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei.
    • The behaviour of quarks, which are the fundamental building blocks of matter along with leptons, can shed light on the difference between matter and antimatter.
    • Since they are unstable, they will “decay” — fall apart — into other more stable particles at some point during their oscillation.
  • Wildlife Conservation Efforts

    Firefly Bird Diverters’ to save the Great Indian Bustard (GIB)

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Great Indian Bustard

    Mains level: Not Much

    The Environment Ministry along with the Wildlife Conservation Society (WCS) India has come up with a unique initiative a “firefly bird diverter” for overhead power lines in areas where Great Indian Bustard (GIB) populations are found in the wild.

    Try this PYQ:

    Q.Which one of the following groups of animals belongs to the category of endangered species?

    (a) Great Indian Bustard, Musk Deer, Red Panda, Asiatic Wild Ass

    (b) Kashmir Stag, Cheetah, Blue Bull, Great Indian Bustard.

    (c) Snow Leopard, Swamp Deer, Rhesus Monkey, Saras (Crane)

    (d) Lion Tailed Macaque, Blue Bull, Hanuman Langur, Cheetah

    Great Indian Bustard

    • The GIB is one of the heaviest flying birds and can weigh up to 15 kg which grows up to one metre in height.
    • In July 2011, the bird was categorised as “critically endangered” by the International Union for Conservation of Nature (IUCN).
    • It is considered the flagship grassland species, representing the health of the grassland ecology.
    • For long, conservationists have been demanding to secure this population, warning that the bird might get extinct in the coming decades.
    • It would become the first mega species to disappear from India after Cheetah in recent times.
    • Till the 1980s, about 1,500-2,000 Great Indian Bustards were spread throughout the western half of India, spanning eleven states.
    • However, with rampant hunting and declining grasslands, their population dwindled.

    Bird Diverters

    • The diverters are called fireflies because they look like fireflies from a distance, shining on power lines in the night.
    • GIBs are one of the heaviest flying birds in India. Therefore, when they encounter these wires, they are unable to change the direction of their flight.
    • Death is most cases is due to impact with the wires and not due to electrocution.
    • The diverter will not only save GIB but other species of large birds, including migratory birds.

    Why such a move?

    • GIB is one of the most critically threatened species in India, with less than 150 birds left in the wild.
    • A report has pointed out that power lines, especially high-voltage transmission lines with multiple overhead wires, are the most important current threat for GIBs in the Thar region.
    • They are causing unsustainably high mortality in about 15% of their population.
  • Global Geological And Climatic Events

    What is Winter Solstice?

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Winter Solstice

    Mains level: Summer and Winter Solstice

    Yesterday, December 21, was Winter Solstice, the shortest day of the year in the Northern Hemisphere. In the Southern Hemisphere, conversely, it was Summer Solstice, the year’s longest day.

    Try this MCQ:

    Q.On 21st June, the Sun

    (a) Does not set below the horizon at the Arctic Circle

    (b) Does not set below the horizon at Antarctic Circle

    (c) Shines vertically overhead at noon on the Equator

    (d) Shines vertically overhead at the Tropic of Capricorn

    Why are the hours of daylight, not the same every day?

    • The explanation lies in Earth’s tilt.
    • And it’s not just the Earth — every planet in the Solar System is tilted relative to their orbits, all at different angles.
    • The Earth’s axis of rotation is tilted at an angle of 23.5° to its orbital plane.
    • This tilt — combined with factors such as Earth’s spin and orbit — leads to variations in the duration of sunlight than any location on the planet receives on different days of the year.

    Impact of the tilted axis

    • The Northern Hemisphere spends half the year tilted in the direction of the Sun, getting direct sunlight during long summer days.
    • During the other half of the year, it tilts away from the Sun, and the days are shorter.
    • Winter Solstice, December 21, is the day when the North Pole is most tilted away from the Sun.
    • The tilt is also responsible for the different seasons that we see on Earth.
    • The side facing the Sun experiences day, which changes to night as Earth continues to spin on its axis.

    Un-impacted regions

    • On the Equator, day and night are equal. The closer one moves towards the poles, the more extreme the variation.
    • During summer in either hemisphere, that pole is tilted towards the Sun and the polar region receives 24 hours of daylight for months.
    • Likewise, during winter, the region is in total darkness for months.

    Celebrations associated with the Winter Solstice

    • For centuries, this day has had a special place in several communities due to its astronomical significance and is celebrated in many ways across the world.
    • Jewish people call the Winter Solstice ‘Tekufat Tevet’, which marks the start of winter.
    • Ancient Egyptians celebrated the birth of Horus, the son of Isis (divine mother goddess) for 12 days during mid-winter.
    • In China, the day is celebrated by families coming together for a special meal.
    • In the Persian region, it is celebrated as Yalda or Shab-e-Yalda. The festival marks the last day of the Persian month of Azar and is seen as the victory of light over darkness.
    • Families celebrate Yalda late into the night with special foods such as ajeel nuts, pomegranates and watermelon, and recite works of the 14th century Sufi poet Hafiz Shirazi.

    In Vedic tradition

    • In Vedic tradition, the northern movement of the Earth on the celestial sphere is implicitly acknowledged in the Surya Siddhanta.
    • It outlines the Uttarayana (the period between Makar Sankranti and Karka Sankranti). Hence, Winter Solstice is the first day of Uttarayana.
  • Urban Floods

    Bihar to change Kosi’s course to save the ancient site

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Kosi River

    Mains level: Floods in India

    The Bihar government will try to divert the course of the mighty Kosi River in Bhagalpur district to save an archaeological site discovered recently.

    Tap to read more about the Himalayan Drainage System:

    Drainage System | Part 3

    Kosi River: The Sorrow of Bihar

    • The Kosi is a trans-boundary river which flows through Tibet, Nepal and India.
    • The river crosses into northern Bihar, India where it branches into distributaries before joining the Ganges near Kursela in Katihar district.
    • Its unstable nature has been attributed course changes and the heavy silt it carries during the monsoon season, and flooding in India has extreme effects.
    • It is also known as the “Sorrow of Bihar” as the annual floods affect about 21,000 km2 of fertile agricultural lands thereby disturbing the rural economy.

    Why change its course?

    • Several priceless artefacts have been found at the Guwaradih village in Naugachhia sub-division of Bhagalpur district during the excavation of a mound.
    • These items could be 2,500-years-old and could be of interest for historians if conserved.
    • The historical sites are facing threats from the Kosi floods.
    • The Kosi currently flows around 300-400 metres from the site, while its old course is about two kilometres from the village.

    Threats posed by the move

    • Environmentalists have warned that changing the Kosi’s course could be disastrous for Bihar as seen in 2008.
    • At that time, the river had breached its mud embankments at Kushaha in Nepal.
    • The Kosi frequently changes its course naturally. If its course is artificially changed, it will cause floods and erosion in new areas, leading to massive displacement of people.
    • It then caused extensive damage to life and property downstream in five densely populated districts of northeast Bihar.
    • Some 500 people were killed and four million rendered homeless.
  • Festivals, Dances, Theatre, Literature, Art in News

    Festivals in news: Chillai Kalan

    Note4Students

    From UPSC perspective, the following things are important:

    Prelims level: Chillai Kalan

    Mains level: Not Much

    People in the Kashmir valley are finding unique ways to celebrate the start of ‘Chillai Kalan’, a local term for the 40-day period of harshest winter that begins annually from December 21.

    Tap here to read all about:

    Festivals, Dances, Theatre, Literature, Art in News

    Chillai Kalan

    • Chillai Kalan is the coldest 40-day period of harsh winter of winter in the Jammu and Kashmir region.
    • It is traditionally defined as a seasonal period of harsh winter accompanied by a change in increase in both frequency and quantity of precipitation usually snow.
    • It begins from December 21 and ends on January 31 next year.
    • It is followed by a 20-day long Chillai-Khurd (small cold) that occurs between January 31 and February 19 and a 10-day long Chillai-Bachha (baby cold).
    • According to Persian tradition, the night of 21st December is celebrated as Shab-e Yalda-“Night of Birth”, or Shab-e Chelleh “Night of Forty”.

    Its’ celebration

    • In the Persian tradition, the night of December 21, the longest of the year, is celebrated as Shab-e-Yalda (night of birth) or Shab-e-Chelleh.
    • Dozens of netizens from Kashmir named it the ‘Pheran Day’, after the long woollen gown worn during the winters in Kashmir.
    • Use of a traditional firing pot called Kangri increases.
    • Tap water pipelines partially freeze during this period. The Dal Lake also freezes.
    • The famous tourist resort of Gulmarg receives heavy snow which attracts skier’s from every part of the world.