A good previous sport of carrom has actually stood the check of time. Set up a board and other people round will flock to it whereas practising their finger gymnastics. You could not have seen however the sport typically begins with an underappreciated ceremony: a pinch of magic powder strewn over the board that one way or the other energises the sluggish cash, serving to them glide easily with only a tiny push.
What did that little bit of powder do?
Fixing friction
Friction is a barely seen drive that surrounds us and slows us down each time we transfer. Isaac Newton instructed us a very long time in the past that if one thing strikes, it’s going to proceed to take action except stopped. Then why doesn’t a automotive simply proceed shifting as soon as it has been pushed? That approach we may have simply reached from one place to a different with out spending any cash on gasoline – and we wouldn’t have to fret if its worth is rising or falling.
The cause is friction. Even if we make roads as clean as attainable, there’ll at all times be some friction that will sluggish the automotive. The invisible air additionally creates friction for aeroplanes and birds. The tough half even for our rockets is the part when they’re getting out of the earth’s ambiance. The air’s friction creates loads of warmth – the similar warmth you generate while you rub your palms in opposition to one another on a chilly day. In outer area, there isn’t any air and spacecraft transfer extra simply, typically for very giant distances with only one push.
Where does this friction come from?
Any floor – similar to a carrom board or your desk – could appear to be utterly clean and straight, however that isn’t actually the case. In reality, no completely uniform floor exists in the universe . If you take a look at any floor very intently, you’ll discover tiny protrusions: mainly a couple of locations that have bumps and others that have dips, like a camel’s again.
The surfaces of a carrom board floor in addition to a carrom coin even have bumps and dips. When the coin tries to maneuver on the board, the bumps and dips on each surfaces will hit one another, slowing the coin. This is the friction at play. Friction may also come up if there are issues to stay on each surfaces, like some oily dust. In quick, friction arises as a result of of forces or interactions between two surfaces.
Think of the carrom coin as a automotive shifting on a highway. If the highway is clean, the automotive will transfer simply. But if there are bumps and dips, the tires may have a tough time shifting, and decelerate the automotive. The rougher the floor, the extra friction there’s.
We repair a damaged highway by filling up the potholes. Similarly, that little bit of high-quality powder fills up all the tiny invisible holes in your carrom board, after which the cash transfer simply.
Dosa pan and air tracks
You could surprise: isn’t there a easy approach of eradicating all friction? Well, folks have discovered wonderful methods to do that. The easiest model is one thing you’ve got been doing at residence, and for a protracted very long time. If you’ve got ever made dosa or some besan chilla, you’ll have sprinkled some water on the sizzling pan earlier than or after. The water droplets transfer on the pan as in the event that they don’t have any friction. This is commonly to verify if the pan is sizzling sufficient. But why does the water not keep on with the pan?
This is as a result of as quickly as the water drops hit the sizzling floor, a skinny layer of steam is fashioned under the drops. So the water drops are actually floating on the pan. Given the surfaces are now not in contact, they’ve little or no friction, permitting the drops to glide round.
In one of the first physics programs at IIT Kanpur, the place I educate, new college students carry out experiments to confirm Newton’s legal guidelines, like the one I discussed earlier. But then Newton’s legal guidelines are solely true when there isn’t any friction. So we have to make objects transfer with out friction first.
One ingenious approach is to conduct an experiment through which an object is made to maneuver on an air observe. Some quantity of air is repeatedly pumped from inside rails utilizing highly effective air blowers. If an object will not be very heavy, it may ‘float’ above the observe by sitting on the air, and transfer as if there isn’t any friction. As a outcome, the college students can now check Newton’s legal guidelines for themselves.
In reality, superfast trains that use the precept of magnetic levitation do the similar factor. Here, the complete passenger practice floats on a powerful magnetic area created by the tracks. There is thus a lot much less friction and the trains can transfer at a terrific pace.
The hassle with electrons
Just like automobiles have a troublesome time shifting over a damaged highway, electrons discover it arduous to maneuver by steel, similar to a copper wire. That is why we pay our electrical payments: so that somebody someplace can repeatedly apply some voltage to the wires, and the electrons cross into them and are available to our homes.
What may very well be stopping electrons inside a fabric? Just as roads have potholes, any materials round us has impurities. For instance, any copper wire may have a hint presence of another metals, similar to zinc or aluminium. The atoms of these metals create ‘friction’ for electrons and make them decelerate as they cross by. So if we’re capable of take away this friction, we can get the wire to conduct an excellent higher present with out making use of any voltage.
You could even be pondering that if we will take away all the impurities from a fabric, we will escape paying electrical payments. Unfortunately, this won’t be attainable. Even although Newton’s legal guidelines are adequate to clarify how carrom cash transfer on a board or automobiles transfer on a highway, they don’t seem to be adequate to clarify electrons.
Here, the legal guidelines of quantum mechanics are at play. A cautious research of quantum mechanics and its functions to supplies tells us there’s one other approach of getting rid of friction for electrons – by the assist of a phenomenon known as superconductivity. If you’re extra excited by studying about superconductors and their fascinating properties, a physics course could also be price fascinated with.
So the subsequent time you curse the rising petrol payments, bear in mind that you aren’t alone. The actual drawback is friction – which automobiles, carrom cash, and even electrons are battling.
The creator is an assistant professor at IIT Kanpur.
