Think

A recent successful bollywood flick “Rock On!!” carried a somewhat popular number - “Socha Hai” (lyrics, written by Javed Akhtar, sang by Farhan Akhtar). This song is a series of 19 questions, pestering the listener, relentlessly and incessantly to give a thought to these questions. The lyricist asks whether you have thought about them, and if not then do so now. Here are the Questions and Answers -

Questions

  1. Why is the sky blue?
  2. Why is water wet (soggy)?
  3. Why is the earth round?
  4. Why is silk soft?
  5. Why is fire hot?
  6. Why is 2 + 2 != 5?
  7. Why are fewer trees left?
  8. Why are there three seasons?
  9. Why aren't there two Moons?
  10. Why is there war in the world and red blood flowing?
  11. Why are there so many borders?
  12. Why does every river flow?
  13. What is light?
  14. Why does snow fall?
  15. Why do friends sulk?
  16. Why do stars break?
  17. Why do clouds have electricity?
  18. Silence cannot be heard.
  19. We cannot see the wind.

Answers

  1. Due to Rayleigh scattering effect. Detailed answer link.

  2. This is a trick question. Water itself is not wet, but makes other things wet as it clings to their surface. This is due to weak bonding between water molecules. It can be attributed to low viscosity and high latent heat of vaporization. Eventually, wetness is a sensation defined specifically about how a thing feels when in contact with a liquid. Detailed answer link.

  3. Due to Gravitational forces. Detailed answer link.

  4. Due to it's molecular structure and material used to create it. Detailed answer link.

  5. "Fire is an oxidation process and this give off heat because electrons in the product molecules are shifted toward the electronegative O or F atoms, and the molecules are more stable as a result. ... Combustion of all types with oxygen are very exothermic because oxygen is quite electronegative and draws electrons to it." Detailed answer link.

  6. This is an attribute of how Arabic numeral system defines numbers.

  7. Rate of deforestation is higher than reforestation. Which can be attributed to increasing pressure on natural resources, exploding human population and their per-capita impact due to better access to technology.

  8. This is according to a specific method of classification. If we change the basis of classification, we can arrive at any number of seasons.

  9. There are multiple moons for several planets, only not for Earth. We only have one, however nothing restricts us from creating another, just for fun.

  10. War's are a result of unresolved political conflicts, and blood flows as it is a liquid.

  11. Number and ubiquity of borders are a result of set of choices made by political heads of different societies. States were formed on the basis of multiple criterion such as language, geographical features, culture etc.

  12. First, all rivers do not flow, as several of them dry out during different seasons. However, when they are not dry, they flow because of gradient of the surface of earth, gravitational force, surface tension, viscosity and weak inter-molecular forces.

  13. Light is an electromagnetic radiation. It has a dual nature. It is both a wave and a particle. Detailed answer link.

  14. Rain and snow are precipitation (wet stuff falling from the clouds). Snow forms instead of rain when temperatures are below freezing (zero degrees Celsius). They fall due to gravitational force. Detailed answer link.

  15. Due to complex set of interactions / circumstances leading to the emotional condition of sulking. Any other reason?

  16. Stars die when they run out of fuel. Simple. Detailed answer link.

  17. Due to friction between particles in cloud, they gather charge. The big clouds get a negative charge and the small ones get a positive charge. Eventually the potential difference is large enough to overcome the dielectric strength between earth and clouds, leading to the discharge. Detailed answer link.

  18. This is a limitation of our ears. (inability to near ~0 dB, Details link)
  19. This is a limitation of our eyes. (inability to see transparent objects).

There. If you have better or more accurate answers, mention in comments.

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US

p.s. – yes, the movie’s title contains not one but two exclamation marks!!. And Google knew most of the answers but not all. So there.

UPDATE #1 - Answer 18 updated to a sound level ~0 dB from 20 dB (earlier confused with 20-20000 Hz range).