Question of the Week

B R Sitaram

Here are the answers to last month’s questions!

Q 1. Lunar calendars are based on 30-day months and 12 such months give you only 360 days. Does this create a problem? How is it solved?
A. It does create a problem. If we do not do something about it, a lunar calendar will very quickly go out of step with the solar calendar. This will result in festivals that are celebrated according to the lunar calendar being held in the wrong season! This is corrected by adding an extra month (called an intercalary month) every few years, so that the lunar calendar is brought back in step with the solar calendar. In the Hindu calendar, these extra months are called “Adhik maas”; in 2018, for example, an extra month (adhik jyaishta) was added. In such years, there will be two months with same name, one with the qualification “adhik”.

Q 2. A common claim on WhatsApp and Facebook is that ancient Indian Rishis knew about the existence of nine planets (nava gruha) for millennia, while European astronomers discovered them only after the discovery of the telescope in the 17th century. Why is this claim absurd?
A. To see the absurdity of the claim, all you need to do is to list out the nava gruha. They are the Sun, the Moon, Mercury, Venus, Mars, Jupiter, Saturn, Rahu and Ketu. Of these, 4 are not planets! Only the remaining 5 (Mercury to Saturn) are planets! These were known to astronomers all over, including in Babylon, Greece, China and Egypt. What we knew was exactly what every one else knew! And, please note that the Earth was not considered a planet, neither in India nor anywhere else.

Q 3. What is wrong with the phrase “burning calories”?
A. Calories are a unit of energy! You cannot burn a unit, anymore than you can destroy a centimetre. What you can do is to convert energy from one form (in this case, chemical energy) into other forms (work and heat). And while this requires the oxidation of glucose, it is certainly not burnt!

Q 4. We make it a point to make young children realize that left, right, front and back are all relative to the observer. For example, if I am standing facing you, my left is your right and vice versa. However, we rarely (if ever) talk about ‘up’ and ‘down’ in the same way. Are they relative or absolute? Is it OK never to talk about ‘up’ and ‘down’ in this way?
A. Actually, ‘up’ and ‘down’ are also relative. For example, ‘up’ for me is a very different direction as compared to ‘up’ for a resident of New York! This simple idea seems to be unknown to many! Many children (and some adults), when they realize that the earth is round wonder why people on the other side of the earth do not fall down; they do not realize that ‘down’ is always towards the centre of the earth (if you are on the earth) and hence there is no question of falling down! This lack of understanding often leads to serious misunderstanding; a common question that I have been asked is why the earth, while revolving around the sun, does not fall down (down here meaning towards the bottom of the page!) Why then do we not talk about this with young children? The point is, if I can see you, as happens with a teacher and her students, my ‘up’ is the same as your ‘up’! Since concepts like left, right, up and down are taught only at a very young age, and we never revisit the idea later on, many students grow up with the feeling that there is only one “up” direction!

Questions for this month

  1. One of the most common musical instruments that you see in concerts is the harmonium, especially in Hindustani music concerts. In fact, when a student goes to learn vocal music, she is often made to learn the harmonium also. However, many purists consider the harmonium to be totally inappropriate for Hindustani classical music. Why is this so?
  2. Very often, we see two planets very close to each other in the sky. For example, on November 24, Venus and Jupiter will be very close to one another. What are the consequences of this happening? What are the chances of their colliding with each other?
  3. Why does a peacock dance in the monsoon season? Why does a snake move from side to side in front of a snake-charmer?
  4. You are planning to send a message to your spouse/boy friend/girl friend on Valentine’s Day. You decide to be biologically correct in the choice of image on your greeting card. What part of the body will your card show to express your love for the recipient?

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