The Official Cricketweb Science Thread!

[luckyeddie]

Who coined the term reverse swing? I think it was Imran, but it would be good to have it verified.

Why does a ball reverse swing?

I'm afraid that you will have to go back quite a bit further than the early 1990's - the tour which had Alan Lamb up in arms about 'one or two things'.

I have studied film of many fast bowlers over the last 30 years and (unless I am mistaken) the 'first' exponent I ever saw of reverse swing was Sarfraz Nawaz with his 'in-ducker'.

As far as 'who first used the term "reverse swing"', that's more difficult. It's a term which has crept into cricket in the last 10 years and everyone uses it. I have conducted searches through my cricket books and the internet and cannot find a single reference to the term before about 11 years ago.

There was a scientific study of the mechanics of cricket ball flight published in 'New Scientist' in 1980, and this deals with 'smooth v rough' sides of the ball, but the modern phenomenon is 'wet v dry'.

I would guess that the first time anyone discovered the phenomenon would have been a total accident. When I was at Derbyshire's indoor nets about 30 years ago, it was like an old 'nissan hut' - a prefabricated structure with a metal roof. In winter, it used to get pretty steamy in there with plenty of condensation.

I could envisage a scenario where a ball had been 'left behind' in there, and a damp or wet area of condensation had formed overnight (say under an old polythene sheet). The next day, someone comes in for a 'net' and finds the ball. One side's dry, one side's heavy with water. The bowler holds the ball as if to swing the ball conventionally, delivers it and it goes 'the other way'.

Now, it wouldn't surprise me if someone (e.g. Sarfraz down at Northants) discovered this phenomenon quite by accident. It would then become a closely-guarded secret. Unfortiunately for bowlers, the whole issue was blown wide open in the early 1990's with accusations, counter-accusations, recriminations and the like.

The 'mystery ball' was no more, and scientific studies eventually confirmed the reason for reverse. Not (necessarily) ball-tampering, but the 'loading up' of one side of the ball with perspiration.

Didn't really answer your question Roy, but I had fun researching it as much as I could.
Did it answer Mr Perko's? Not totally, but there are many studies which have been performed, and I don't feel right just reproducing their work here. Just use a search engine, plug in 'reverse swing' and away you go. If there are bits you don't understand regarding the aerodynamics and so on, feel free to ask us again.

[Gotchya]

Even at speeds approaching 20% of the speed of light, savings are extremely minimal. In order for true inter-stellar travel to become a possibility, speeds approaching 99.9% of the speed of light would be necessary (or suspended animation for the travellers).

Yes thats true. Additionally you would obviously appreciate the fact that as the mass in concern approaches the speed of light, the mass also becomes large, very larg, it would need a very large force to push it over the 'c'. So theoretically this too is a scientific impossibilty.

[Gotchya]

yeah well to put it simply, the aerodynamics explained simply would be :
suppose you have a cricket ball with a rough and a smooth side,
Now the scientific explanation would be that air sticks to one side more then it does to the other, so as air performs its 'turbulences' the ball swings in the opposite direction.

[royGilchrist]

On the subject of reverse swing, wont it be useful to make the laws regarding ball tampering a bit lax, which make the disparity between ball and bat a little less, especially on the docile subcontinent pitches.

Acutally I kinda realize this is a stupid suggestion, but still would be interested to hear a few arguments opposing it.

BTW, relaxing the ball tampering law could mean, bowlers can use glycerine (Im dont remember the name of an aussie who in the 70s allegedly used glycerine once, Max Walker maybe or Bob Massie?), or nails (pretending that they are already not used).

As for Reverse swing, Im pretty sure it was Imran who coined the term reverse swing. To legitimize the rather dubious practices used by fast bowlers. Its widespread among Pak cricketers that the process involving making one side of the ball heavier and rougher involves a lot of dubious stuff like scratching with nails, and was made into an art form by Sarfraz. I think 'reverse swing' was Imran's attempt to give it a name and make it sound like something technical.

[luckyeddie]

I believe that the use of 'additives' to assist swing is used widely in baseball.

Whether this is legal or not I have no idea (flipping rounders - girl's game ).

We used to mess around in the nets with 'Lipsol' (a type of lip gloss, a small smear of which on the flannels would assist shining of the ball). The big giveaway was the bright red smear on your thigh, because it dissolved a little of the colour from the cricket ball's cover.

Has anyone noticed how the new balls used in the current test series swing like crazy, even with both sides shiny?

I think the ball they are using is the 'Duke' as usual, which has the emblem and loads of gold paint on one side only, so it's already pretty unbalanced.

After 10 overs the swing tends to die down, then gets going again after 30-40 (conventional swing). There wasn't much evidence of any reverse swing at Trent Bridge, presumably because of the lushness of the outfield.

[Paid The Umpire]

Here is the 50th post:

I remember that I saw an article about rain, which said that running compared to walking in the rain will get you wetter. Does any one know about this?

Well, do ya?

[luckyeddie]

Amazingly enough, there is a scientific answer to this problem, and it is extremely complex. It depends (I bet you knew that I would say that) upon a number of factors.

Your height, basic shape - these dictate your cross-sectional area.

Your speed - this dictates how long you are out in the rain, but it also alters the angle of the rain relative to you.

Wind speed = this also alters the angle of the rain relative to you

Wind direction = this alters your profile relative to the direction the rain is coming from and consequently affects your cross-sectional area which is presented to the rain.

Raindrop size - this dictates how fast the rain is falling, but not necessarily how much rain is falling.

Rainfall rate (amount of rainfall per hour).

There is no stock answer - sometimes you will get wetter, sometimes you will stay relatively drier, but in general if you can present the smallest cross-sectional area to the direction the rain is coming from, this is going to allow you to remain relatively the driest.

In other words, walk or run at the same speed as the rain in precisely the direction the wind is blowing TO.

I bet you never knew that.

8D

Example - an Olympic sprinter, faced with a 200 metre sprint in a downpour from the wrong direction could be drenched by almost half a litre of water. If he were sprinting in exactly the opposite direction, it would be a mere 50 millilitres (about a good mouthful).

Again, if you want to play, you can find the algorithm by following this link :

http://www.dctech.com/physics/features/0600.php

[David]

that was incredibly cool

[anthonysw]

I will never think about rain the same way from now on

[Gotchya]

Which of these 3 sports will be the hardest or the easiest to play on the moon? Basketball, Soccer or Cricket?

[luckyeddie]

Interesting.

I think that football would be the only sport possible of the 3 named, especially if we were talking about outdoors.

Basketball would be impossible. Six inches of moon dust would reduce the coefficient of restitution (bounce) of a basketball to something approaching zero, thus making dribbling impossible.

The actual size of a cricket arena would have to be enormous. If the average distance from the wicket to the boundary on Earth is (say) 80 metres and the Moon's gravity is approximately 1/6 of that which exists here, then the diameter of the cricket ground would have to be about a kilometre, just to give the batsmen a challenge.
Any smaller and you would just run out of balls. Even at this size, you would be far better lofting the ball into the outfield and having it not quite reach the boundary. Assuming that the average speed of a batsman is around 5 metres per second (and a fielder 7 metres a second), a ball struck to just inside the boundary would reach it in 16 seconds. The batsmen would be able to run 3 whilst the ball was in the air, sorry, vacuum. The fielder would reach the ball in around a minute (if he could find it in the moon dust). His throw would take around 15 seconds to get back to the keeper. In the meantime, the batsmen would have run about 14. Matches would have to be restricted to 5 overs a side, otherwise the scores would be astronomical.

There must be some reason for asking the question. Have you just bought the rights to build the first sporting venue on La Luna ?

[Gotchya]

There must be some reason for asking the question. Have you just bought the rights to build the first sporting venue on La Luna ?

Heck yes, Just wanted to know what would return the best revenues :P
Was just prowling the internet and found this one on a website, interestingly, you say that fottball would be easy, well for one i will say that football alike basketball commands good control over the ball and above all keeping it on the floor, which would be virtually impossible on the moon. Huge arching passes would make life very miserable for the players, on the other hand, the goal keepers would have a party !!

[luckyeddie]

I don't think that I said that football would be easy - in fact it would be very difficult for the reasons you stated.

However, conditions would be perfect for a team like Wimbledon of the 1980's.

[royGilchrist]

this is not directly related to science, but...

LE might take this one...the Philoshophers from continental Europe, Descartes, Kant, Hume were I think called empiricists, and the the philpsophers from Britain like Locke, etc were called by another name, what was that?? Someone brought this up today, and I had forgotten this from the college days, thought I could get a quick answer here.

[luckyeddie]

Most definitely related to science.

I don't think that the distinction you are looking for is Empiricism v somethingelseism, since John Locke himself was most definitely an Empiricist.

An empiricist is one who believes that the fundamental laws of nature (or even the universe because it's the same thing) can be derived from observation and experimentation.

'Empiricist' the word implies fundamentalist (no, not that kind of fundamentalist), as in 'getting to the fundament or root', or 'empirical formula'.

My first thought was that you might be looking for the grouping of 'non-determinalists'. This really only manifested itself as a mainstream philosophical grouping in the early part of the 20th century and included guys like Nietzsche and Kierkegaard, Dostoyoevski, Sartre and the like, and then I thought "they're not British". Anyway, they were known as 'Existentialists'.

There is no real definition of Existentialism, because the very nature of the philosophy is it's vagueness, i.e. the non-existence of universal truths, specific codes of moral behaviour and the like.

The argument runs along the lines "If there is no god, then all fundamental rules of behaviour are man-made. There is no such thing as destiny, because nothing is pre-determined. If there is no destiny, then all futures are possible".

It then gets a bit deep.
8D

My dilemma is that existentialists claim that there can be no universal truths without preordination.

The trouble is, it is an entire philosophy based upon a single pretext (but aren't they all?).

An existentialist claims that there are no universal truths, however the fundamental building block of the philosophy is based upon a single universal truth (theists and believers in any sort of deity look away now) that there is no god.

If I'm on the right track, let me know. Otherwise, I will go on to discuss Skepticism, Relativism, Phenomenology, Post-modernism, Feminism and the concepts of Buddhism. 8D