SCIENCE CAPSULES

        Let us start with an example.  Consider math and biology teachers working in a school.  Every year, they train students and send to school final examinations.  Some students pass.  Some students do not make it.  Every year, each teacher gets 'percentage of passes' score.      The pass percentages for each teacher for two years are given below.                     Math teacher        Biology teacher    Year I           70/80 = 87.5%       20/20 = 100% Year II          10/20 = 50%         50/80 = 62.5% Total             80/100 = 80%       70/100 = 70%     Here, the denominator is the number of students appeared and the numerator is the no.of students passed. ...

         The aluminium cans that you use to drink not only contains juices and coke but so much science      15000 cans are manufactured in one-second worldwide.  A light and strong container.      We can have spherical containers like fruits.  It requires the least raw material.  (Sphere is the only shape which has maximum volume and minimum surface area).  But it is difficult to manufacture spheres.  And it has only 74% packing efficiency.  That means 26% of space in a box goes waste.      Next, we can think of the cuboid (rectangle area).  Here edges are sharp and weak.  And the packing efficiency is also not good.      Finally, we come to cylindrical containers.  We can rapidly manufacture them.  The packing efficiency is 91%.  The cylinders have a curved surface.  The curved surfaces always have more strength than flat surfaces. ...

         Thomasalwa Edison was trying to make an electric light source.  He tried a thousand materials to act as a filament in the bulb.  He tried Aluminium, gold, carbon fibre and even hair.  On sending Electric current, the filament should be instantly heated up and emit light somewhat similar to day-light and should not melt.  At last, he found 'Tungsten'.  So he invented the world's first incandescent (Non-smoking) lamp.  It lighted up our nights for 100 years.  But now we have moved to LED lights.      Why Edison struggled to invent the electric bulb, for fame, for money, or for soul-satisfaction.      Whatever may be the selfish or selfless motive, it has benefited humanity for a number of years.      Today, New smartphones arrive every now then.  The companies or corporates want to get a big share of the market and mint money.  But, we get phones that are...

        Tom has to decide whether to go to a college or take up a job. SCENARIO I      If Tom belongs to a middle-class family, going to a good college and earning a degree will help his family and his career.  Going to a job straight away will put him in a low-level job.  And he may stick with it for his entire life.  Here education yields more than a job. SCENARIO II      Say, Tom belongs to a rich family.  His father is running an industry employing hundreds of persons.  His father is also ailing at present.  So, for Tom education is not essential.  It is only an ornament.  If he takes up a job in the family business, he will earn valuable experience and move up the ladder in the company management quickly.  He can study through distance education.  Or he can go to part-time classes.  He is not going to lose anything for want of higher education.  Here work-experie...

     Here is a job interview question which forces you to think out of the box.      "It is an ancient invention.  It helps us to see through walls.  It is widely used throughout the world.  What is it?"      The answer is W O D N I W (spelling reversed)      The word "invention" makes us think about "scientific devices".  But sometimes think "out of usual".   How to cultivate the habit of lateral thinking?  Here, I will try to present one procedure.      First, let us take one problem.  You employ a painter to paint the irregular shape of a wall for artistic purpose. How to calculate the surface area of the wall?  How much to pay to the painter?  How much paint to buy? Now, the procedure,       Take six hats in different colours.  White, black, red, green, yellow, and blue.  STEPS:      1. Put on a whi...

       Even in open ground, if you erect light bulbs in all the four corners, the ground will be flooded with light.  But universal space has lots and lots of stars (actually suns).  Then, why the night sky is pitch dark?      To answer this question, we have to go billions of years back.  That is the birth time of the universe.  Long, long back, the matter for the entire universe was contained in a tiny atom.  The tiny dot has zero size, large mass, infinite density.  There was 'big bang', an astronomical explosion.  The entire matter was thrown out.  The universe was born.  The time started to tick.  Explosion temperature begins to cool down.  Galaxies, star systems formed.  They all continue to move and expand like a balloon[due to explosion].  Even today, all celestial bodies continue to move away from us.  The expansion of the universe is the greatest discovery of the cen...

       Yes, if you happen to live on the hundredth floor.  Tall buildings oscillate up to few meters due to wind and earth-quack.  It may be uncomfortable for dwellers.  It may even be dangerous.  There is a physics technique to prevent this vibration.      Tall towers can be considered as an inverted pendulum. It will oscillate with its own natural frequency due to natural forces.  Now select a pendulum of the same frequency and attach a suitable weight.  Hang this pendulum in the top portion of the tower.  When the tower swings in one direction, the pendulum will swing in the opposite direction.  That is, tower and pendulum will execute opposite oscillations.  Hence the building's energy will be dissipated through the pendulum and the swings of the building will come to a stop (damped) quickly.  Hence this pendulum is called 'Tuned mass damper" (TMD). [Matching the frequencies is called tunin...