Question Discussion & Solution

The correct answer is Calcium Carbonate.

Key Points

• The chief component of the nacre that constitutes the pearl is aragonite (CaCO₃).
• Nacre also contains a small amount of conchiolin, a hornlike organic substance (albuminoid) that is the main constituent of the mollusc's outer shell.
• Pearl also contains Magnesium Carbonate(MgCO₃) along with Calcium Carbonate.

Additional Information

• Calcium carbonate is a common substance found in rocks as the minerals calcite and aragonite and is the main component of eggshells, snail shells, seashells, and pearls. 
• The Molar Mass of Calcium Carbonate is 100.0869 g/mol.
• Melting point: 825 °C.

The correct answer is Kuchipudi Dance.

• Yamini Krishnamurti is related to Kuchipudi Dance.

Key Points 

• Yamini Krishnamurti is a Kuchipudi dancer.
• She also knows Bharatnatyam.
• A Passion For Dance is her autobiography.
• Kuchipudi:
  • It is the classical dance of Andhra Pradesh.
  • Kuchipudi derives its name from the Kuchipudi village of Andhra Pradesh.
  • Kuchipudi exhibits scenes from the Hindu Epics, legends and mythological tales through a combination of music, dance and acting.
  • Like other classical dances, Kuchipudi also comprises pure dance, mime and histrionics but it is the use of speech that distinguishes Kuchipudi’s presentation as dance-drama.
  • ‘At times, even though the dramatic situation did not demand, solo dancing was being presented to punctuate the presentation and to enhance the appeal. One such number is tarangam inspired by the Krishna-Leela tarangini of Teerthanarayana Yogi.
  • There are now two forms of Kuchipudi
    • The traditional musical dance drama 
    • The solo dance.
• Bharatnatyam is the classical dance of Tamil Nadu.

CONCEPT:

Nuclear reactor:

• It is a device in which a nuclear reaction is initiated, maintained, and controlled.
• It works on the principle of controlled chain reaction and provides energy at a constant rate.

EXPLANATION:

• Nuclear Fuel: It is a fissionable material to be used for the fission process to take place. Therefore option 1 is correct.
• Commonly used fuels in a nuclear reactor are U233, Enriched U235, Pu239 etc. 
• Generally, uranium oxide pellets are inserted end to end into long hollow metal tubes constituting the fuel rods.
• When slow neutrons interact with the fuel, the fission starts, and the energy is released. 

Additional Information

• The moderator's function is to slow down the fast-moving secondary neutrons produced during the fission.
  • The material of the moderator should be light and it should not absorb neutrons.
  • Usually, heavy water, graphite, deuterium, and paraffin, etc. can act as moderators.
• Controller: These are made with neutron-absorbing material such as cadmium, hafnium or boron, and are inserted or withdrawn from the core to control the rate of reaction, or to halt it. 
• Lubricant: Lubricant has shown that it is possible to produce materials capable of lubricating some reactor components.
  • In order to further the development of such lubricants, the U.K.A.E.A. and the nuclear manufacturing groups have co-operated in providing lubricant manufacturers.

• 9.8 m/s² is the value of acceleration due to the gravity of the surface of the Earth.
• The acceleration which is gained by an object because of the gravitational force is called acceleration due to gravity.
• Its SI unit is m/s²

The correct answer is Punjab.

• Bhangra Dance is related to Punjab.

Key Points

• Bhangra is a type of traditional dance of the Indian subcontinent originating in Sialkot in the Majha area of Punjab.
• The dance was associated primarily with the spring harvest festival Baisakhi. 
• Bhangra referred both to formal male performances as well as to communal dancing among men and women.
• D.J. Rekha was one of the first South Asian women to bring popularity to Bhangra in the U.S.

Additional Information

• Garba is a type of Indian dance commonly performed at festivals and on other special occasions in the state of Gujarat.
• Kerala is popular for its two classical dance form 'Kathakali' and 'Mohiniyattam'.
• Folk dances of Assam include the Bihu, the Bagurumba, the Bhortal, the Satriya, Naga dance and the Ojapali.
• Odisha's famous dance forms include Odissi, Chhau, Gotipua, Danda Nata, Sambapuri, Dalkhai, Chaitighoda, and Medha Nacha.