Tag: science & technology

Guru Ram Das, the fourth Sikh Guru, founded Amritsar in 1577. The city grew around the Harmandir Sahib (Golden Temple) complex. The distractors are other Sikh Gurus - Guru Amar Das was his predecessor, Guru Arjun Dev his son, and Guru Har Gobind his grandson.

Flight recorders (black boxes) are painted bright orange with reflective tape to make them easier to locate after crashes. The term 'black box' refers to their function, not appearance. White would blend with clouds/snow, while black would be hard to spot at night or in wreckage.

China has held the world's largest foreign exchange reserves for decades, exceeding $3 trillion. This reflects their export-oriented economy and currency management policies. India has significant reserves but ranks third globally, while the US and UK hold much smaller relative reserves.

Mercury cannot form amalgams with iron because iron is immiscible with mercury - the two metals do not mix at all. Mercury readily forms amalgams with gold, silver, zinc, and many other metals, which is why mercury was historically used in gold and silver extraction. This is a fundamental chemical property tested in basic chemistry.

Sleeping sickness (African trypanosomiasis) is transmitted by the tsetse fly, which is found only in rural Africa. The disease is caused by parasites of the Trypanosoma brucei species and can be fatal if untreated. Filariasis is transmitted by mosquitoes, smallpox is viral and spreads person-to-person, and anthrax is bacterial from infected animals or spores.

Blood group O individuals can ONLY receive blood from other O group individuals because they have both anti-A and anti-B antibodies in their plasma. Receiving A or B blood would cause a dangerous transfusion reaction. While O is called the 'universal donor' (can give to anyone), they can only receive from other O donors. This is fundamental transfusion medicine.

A seismograph is the instrument used to measure and record the intensity of earthquakes. It detects and records the ground vibrations caused by seismic waves. A barometer measures atmospheric pressure, a hydrometer measures liquid density, and a polygraph is a lie detector. This is basic earth science knowledge.

Sharks have skeletons made entirely of cartilage rather than bone, which makes them lighter and more flexible. This characteristic classifies them as cartilaginous fish (Chondrichthyes), along with rays and skates. Most other fish have bony skeletons (Osteichthyes). Sharks do have teeth (multiple rows), gills for breathing, and a large liver, but no true bones.

Our solar system has 8 planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto was reclassified as a dwarf planet in 2006 by the International Astronomical Union, reducing the count from 9 to 8. This is current astronomical knowledge taught in all basic science curricula.