SCIENCE CAPSULES

          Why should we ignite to start the fire?  Where do the blazing light and heat come from? An inquisitive mind always try to find the answers.  Now we go..     We will consider a simplest combustion or burning reaction.          2H 2 + O 2 = 2H 2 O + heat      Here hydrogen combines with oxygen to form water and release heat.   Suppose we ignite hydrogen gas in a jar, it reacts with atmospheric oxygen; burst into flames; forms water vapour; release of lot of heat and light energy.  This reaction is still used in rockets. BURNING LAID BARE:      Hydrogen molecule has two hydrogen atoms that are bonded together.  So does the oxygen molecules.  These bonds are weaker.  If we supply little heat energy -igniting-the bonds break loose.      Now the loose atoms form a new molecule -water molecule (H 2 O).  The bonds are stro...

          Why we have weakness, madness, possessiveness and soft corner for this yellow metal? SOME ANSWERS  1. It is glittering always.  It does not rust like iron. 2. It is not abundant like water or silver.  Also it is not scarce like diamond or uranium. 3. By adding little copper, you can shape it in any way you want.  One can make intricate jewelry with it. 4. It is portable wealth or property. 5. Its price usually does not nose dive.  It is stable or grows.  It is even take care of money inflation. 6. It is instantly en-cash-able. 7.  On the long run, it does not depreciate and only appreciate. 8. Gold attracts women.  May be due to female hormones. 9. Dowry in the shape of gold ornaments is the main stay in many societies. 10. People believe 'investing a portion of their income in gold' is good strategy. 11. It can be pledged, sold, en-cashed.  In emergency, nothing helps like gold. 12. Banks...

       All the physical bodies have a property called 'inertia' according to the Newton's first law.  That is, a body which is moving in straight line; a body that is rotating or a body at rest, will not change its state easily.  It will try to keep on doing what it is doing.  Even it will hesitate to change its direction.  For humans, inertia can be called laziness.  A man finds it is difficult to change his altitude, ideas, work, character.      A giant wheel that is rotating cannot be stopped all of a sudden.  It requires great effort and long time.      We are exploding atom bombs now and then, earth gets tremors and earthquake now and then.  Did they disturb the rotation of  the earth in any way.  No, not at all.  The earth is huge and heavy.  It is rotating at the speed of 1000 km per hour.  Heavier the body, greater the inertia.  Hence the man made forces is n...

          On a online store X, a product costs 200 dollars and it has 15 positive reviews.  Another online store Y features the same product for a price of 250 dollars with 32 positive reviews.  Which one to buy? Little Math:      Find the product of prices and reviews .  Then take the square root of the answer.  Do it for the both the stores. For store X:      Square root of (200*15) = 54.77 For store Y:      Square root of (250* 32) = 89.44 89.44 is greater than 54.77.  Hence go for the store Y.  These numbers called geometric mean.  This 'measure' is used to compare widely different values like 200 and 15.  Average stand best for closely related numbers like 120, 125, 101. SOME MORE USES OF GEOMETRIC MEAN 1. Making square out of rectangle:      Say, 18 cm and 2 cm are the sides of a rectangle.  Find the geometric mean of them.   ...

                     Say, a lady by name Mary makes 'home made chocolates' in a hill station called Ooty.  She wanted to fix the price.  So she begun to experiment.  At the most, she can make 10 kg of chocolates per day.  First, she put the price at 1000 rupees per kg.  No takers.  It proved costly for both locals and tourist.  She changed the price to 750/ kg.  Some 3 or 4 kg sold daily.  Then she drastically reduced the price to 250/kg.  (even though she incurred loss). The chocolates sold like hot cakes.  There was a demand for more than 15 kg a day.  She was not able to cope up with the demand.  Next, she  priced the chocolates at 600 per kg.  That included some decent profit.  Now, around 10 kg  sold everyday.  She was happy 'for ever'!.       "A thing is perfectly priced when supply equals demand".   Supply-...

A  micro story:      In a famous Indian temple, the stepping stone asked the main deity, "people are walking on me without respect but worship you with great respect. why?  Even though we came from the same stone."     The deity replied, " The artisan made just two or three cuts to make you.  But I received so many blows and cuts with chisel and hammer.  I bore them all.  My eyes, nose and all my features, dress, jewels are chiseled and carved out intricately by the artisan.  That is why I get the respect that I deserve".      Lesson 1.  The masterpiece or statue is hidden in the stone.      Lesson 2: It takes so  much hard work with devotion and patience to carve out the deity.      Every marble or stone has a beautiful sculpture.  It is up to us to carve it out.      We know 'white contains all the colours'.  So does the white paper. Usin...

          Take hot potato.  Cut it into four pieces.  Keep them on a plate.  Blow air on them using a fan.  It will cool down quickly.  By cutting potato into pieces, we increase surface area.  Since more area is in contact with atmosphere, potato can easily transfer the heat to the air in the atmosphere.  If we blow air with a fan, it will further aid the transfer of heat.     So the 'principle of cooling' is , 1. increase hot surface area. 2. blow air.      In a tropical country like India, you might have observed this scene in a tea shop. To cool the tea, the person raises the hot cup of tea as high as possible in one hand, in another hand he holds another empty cup as low as possible.  He repeats the process a number of times.  Surprisingly there is no word for this process in English.  We will see why, a little later.  But Indian languages do have.  By pouring tea fr...