[November Tests 2016 EOYT] England vs. South Africa (12/11/2016)

[smartcooky]

Speaking of 12 year old science pupils, if you are running at full speed and throw the ball flat, the ball would not keep up with the passer when watched from the side.
Friction would make the ball appear to slow down vs the passer. Friction would affect the passer too but he keeps putting energy to keep up the speed, the ball does not.
As someone who likes to educate you'd appreciate getting the science right, i assume.

What you are talking about is Air resistance. While it is a force that affects objects that move through the air, and there will be some influence on a moving football, it really only applies in any practical sense to fast-moving objects like aeroplanes, and would only be naked-eye detectable in slow moving small objects that had a long flight time, such as a kicked football. The influence of air resistance on a football travelling for fractions of a second at under 10m/sec is so tiny it can be discounted in a case such as this, particularly as the surface of the ball is so smooth. The shape of a rugby ball (a prolate spheroid) is also a variable that, while it influences the flight of the ball, would be minuscule.

I did some back of the envelope calculations based on the drag co-efficient formulae on this page (Which is quite interesting as it talks about air resistance with footballs)...

http://www.forbes.com/sites/chadorz...oying-physics-of-air-resistance/#1589946910bd

A rugby ball, not spinning or tumbling, but presenting its widest possible aspect (best case for maximum air resistance), travelling 10m/sec (that's 10 second 100m pace) on a 1 second flight (longer that the time this ball spent in flight), would slow down over the one second period by 0.048 m/s (so it would slow down from 10.000 m/s to 9.952 m/s.

You would need a Doppler radar to measure that; you would certainly have no chance of detecting that change with the unaided eye

 

[Ragey Erasmus]

Thank you for clearing that up, I grew up in forms not years.
Ragerancher, can you take your one man crusade to private mail please, your constant desire to get into a battle with cooky over semantics and nit picking rules etc either needs it's own thread or a PM. It's getting rather dull having another thread filling up with your private war. Go ahead and have it by all means as it's obviously pretty important to you but please don't clog up the interesting threads with it mate.

Cooky was that one that started it and he was the one implying both ignorance of the rules and a gn understanding of physics less than an A level student... What's getting dull is cooky coming and lecturing people in a condescending way every single time. I thought the ball left the hands forward and on closer inspection changed my mind. Cooky decided to interpret that as I didn't know what the rules were and didn't understand that a ball would retain the momentum of the running player.

 

[TRF_heineken]

We were just beaten by the better team. No other way to discribe it DDA and Whiteley were actually pretty good today. Beaten by the better team. England take a bow you are a class outfit!

DDA, Whiteley, Lambie, PSDT and Koch were all absolutely pathetic. Yes we were beaten by a better team.

DDA is terribly out of form and all would agree that he's AC's lovechild.

Whiteley is anonymous when games are tight and an attrition battle in the pack. The only time he did something noteworthy was his run down the touchline for Goosen's try.

Lambie is starting to make it a habit of kick-off direct into touch. And his defence were woeful as well, and he was up against the smallest guy in the English team. His goal kicking was also poor.

PSDT was yet again shown that he's not a flanker. Just like in the Japan game... He can't defend the first pillar channel and he can't keep up with the other flankers.

Koch, he missed about 8 tackles, along with PSDT they were dreadful in defence.

Oh, and our Wingers, They looked terribly slow, and their handling was horrible, together they were the direct cause of 2 of England's tries.

I personally don't think the current Bok woes are related to politics. The team is not playing as a cohesive unit in defence or attack mode. There are obviously some serious coaching and leadership issues.

I don't think Coetzee was unqualified for the job, but the defensive qualities of his Stormers side a few years ago certainly don't seem to have found their way into this Bok team.

If we perform poorly in the next few games, he should resign. Hey, sometimes things don't work out, like Mourinho at Manchester United, and Mickey Arthur with Australia's cricket team (he was great with SA beforehand and is doing a great job with Pakistan in Tests)

Are you serious? The whole process of appointing the bok coach was a farce. First, they made an agreement with HM to end his contract early (and what for? He got us to the semi's where we lost by 2 points against the AB's). HM still had a year left on his contract, Also note that since his termination, he hasn't been in SA rugby circle whatsoever, and hasn't even made a single statement about the state of SA Rugby. My guess is some form of confidentiality agreement was reached.

Then SA Rugby basically head-hunted AC, overlooking many other coaches (Eddie Jones was actually also a contender as he was with the Stormers at that time). Along with AC, we still have Mzwandile Stick as backline coach, and you can just see the pedigree in our performances.

I saw minor glimpses of improvement in the first half, and could see some minor technical things that were better than in the past. But overall, our gameplan, player selection and lack of adaptation cost us the game.

We had 5 jumpers in the lineout, yet we never competed when it was an England throw-in. WHY??? We had such a big pack, but only tried to maul 3 times. WHY??? And why didn't we kick the ball out?? Brown and Billy had a field day running the ball back. I just don't understand what our tactics are anymore.

Well looking at it again carefully it does seem flat, however you really should stop being such a condescending prick. I have a masters in engineering so know about this stuff a "12 year old science pupil" would understand.

I seriously don't get why you go out of your way to launch some sort of attack each time Cooky tries to explain the rules. I can get his frustration in repeating himself over and over in the same thread too. He explained why it wasn't forward, which the referee on field and the TMO agreed on, and that decision won't change. The ref specifically went upstairs to check that pass, and he was happy that it didn't breach any laws. So Cooky's assessment on the incident is correct, so why keep on defying what he's saying??

 

[The Jones Boy]

Cooky was that one that started it .

Mate, do you know how lame that bold part sounds... it's like a little kid telling tales.
This is hardly the first time you and Cooky have been rowing on the threads is it?
Come on...???
"fess up", you two have been tangling all too often and messing up threads with your ongoing *****ing at each other.
Yes Cooky can be a condescending creature, agreed, but thats how he is, just ignore him if it offends you. Thats what 'grown ups' are meant to do.
In much the same way as the rest of us ignore 'Kiwi' in his many guises.

Secondly it's the internet. All too often he might well be sitting there with his tongue firmly in his cheek and a wry smile on his face knowing full well that if he couches his commentary in a certain way then it will bait you and you will fall for the bait and start yet another little ranting war that messes up an otherwise enjoyable thread.
If you two were in person, you may well say the same things but with the inflection of humour that can come from vocal intonation, body language, facial expression and a comic action like a slapstick element these comments have none of the negative appearance we attribute to them when they are just black and white symbols on a screen. That's when 'we' attribute all manner of pre-supposed and/or alleged insult and hurt that simply must be refuted immediately and to the enth degree.

Contrary to popular belief, 'There is no hardman action button on the internet.'
Step back, breathe, let the anger subside, and if you are still suitably piqued at his commentary, take it to PM mate.
Apart from this unfortunate feuding you're a bloody good poster.
Lets have more of the good stuff.

 

[Cruz_del_Sur]

What you are talking about is Air resistance.

I wrote friction, and i meant friction. If you need to re-write it because you are unfamiliar with the term, do so, but do not pretend to correct me.
Let me be absolutely clear: on this subject, i can and will educate you, not the other way around.


And no, you do not need any radar to see it. Any sideways curvature the ball does when kicked (to give an even more obvious example) needs friction to occur.

For someone so eager to educate others you sure get a lot of the facts wrong.

 

[ncurd]

I lost interest in the game about 50-60mins in and was only half watching for the rest of the game. It was a pretty crap game skills wise due to weather and clearly wasn't going to be a nail biter either.

I seriously don't get why you go out of your way to launch some sort of attack each time Cooky tries to explain the rules.

Here's my issue it's Cooky decides to explain the forward pass rule (which most of us understand, and he should know this it's not new forums members having this conversation) which the decision goes against England. However at the time in the thread there was complete misunderstanding of what constitutes a knock on (which went against SA). It would of been far more useful to explain that than go over the forward pass rules again. There does appear to a consistent attempt to show the larger group they are wrong.

On the pass itself it's pretty flat in slow motion from angle Cooky showed so I'm agreement it wasn't forward. However I'm slowly becoming of the opinion that it should be forward if it goes beyond the gain line at the point the pass is released, Its how most laymans understand the rule and it would stop this nonsense.

 

[McTallshort]

bet you lot are a barrel of laughs on the ****.......

 

[TRF_heineken]

I lost interest in the game about 50-60mins in and was only half watching for the rest of the game. It was a pretty crap game skills wise due to weather and clearly wasn't going to be a nail biter either.Here's my issue it's Cooky decides to explain the forward pass rule (which most of us understand, and he should know this it's not new forums members having this conversation) which the decision goes against England. However at the time in the thread there was complete misunderstanding of what constitutes a knock on (which went against SA). It would of been far more useful to explain that than go over the forward pass rules again. There does appear to a consistent attempt to show the larger group they are wrong.

On the pass itself it's pretty flat in slow motion from angle Cooky showed so I'm agreement it wasn't forward. However I'm slowly becoming of the opinion that it should be forward if it goes beyond the gain line at the point the pass is released, Its how most laymans understand the rule and it would stop this nonsense.

What is frustrating, is that the incident was queried, and Cooky as he has always done, used the laws, along with illustrations as an IRB referee himself, to explain the pass. When I first saw the replay of Venter's pass, I immediately saw that Venter's hands were going into a backwards motion as he released the ball, and then knew that no matter how the ball then travelled afterwards, it would be deemed as a fair and legal pass.

This is thanks to Cooky that has educated me in the past on passes such as this.

Now I don't care if there are animosity between members and Cooky, or the way in which certain posters feel that Cooky is being condescending or rude or obnoxious. For the Majority of this Forum he is providing a great service in assisting us in understanding the laws and how it's being applied in matches. If the very few members don't like what he's saying, they have the right to use the ignore function to not see his posts, instead of going on over technical aspects.

Cooky didn't make these laws himself. He is not the Rugby Lawmaker. But as an active member of the IRB's referee association he has a lot more knowledge and experience on these matters than anyone else on this forum.

 

[Ragey Erasmus]

Mate, do you know how lame that bold part sounds... it's like a little kid telling tales.
This is hardly the first time you and Cooky have been rowing on the threads is it?

You said I went looking for a fight, I didn't. I made comment and Cooky was the one who came looking for a fight.

As for why I argued, it's because I disagreed that the ball left his hand backwards from the offload, not some interpretation of the rule. I have since analysed it and agree with Cooky that it was flat rather than forward but did not like the way he decided to make the petty jabs when the issue wasn't whether I understood the rule or basic physics but just purely thinking the direction of the pass had been forward rather than flat or sideways.

Actually Cruz, you are wrong, the friction you talk about is air resistance as Cooky said. Also a ball curving in the air, disregarding wind, is due to a pressure difference on either side of the ball.

 

[pagliaccio_euforico]

Best part of this thread is people not knowing that air resistance is friction

Has nothing to do with whether or not pass was forward but it's hilarious

 

[LeinsterMan (NotTigsMan)]

Best part of this thread is people not knowing that air resistance is friction

Has nothing to do with whether or not pass was forward but it's hilarious

Not quite that simple, both are Frictional forces (to a degree) but Air resistance isn't the same as friction I believe

 

[pagliaccio_euforico]

Air resistance is to friction as squares are to rectangles

 

[LeinsterMan (NotTigsMan)]

Air resistance is to friction as squares are to rectangles

So not the same.

A cart horse is a horse but you wouldn't run it in the grand national.

 

[pagliaccio_euforico]

So not the same.

A cart horse is a horse but you wouldn't run it in the grand national.

Never said they were the same. But to say that air resistance is not friction is factually incorrect which people have done.

 

[Duck a l'Orange]

So not the same.

A cart horse is a horse but you wouldn't run it in the grand national.

Just because all swans are white, does not mean that all things are white.

All squares are rectangles, but not all rectangles are squares.

All air resistance is friction, but not all friction is air resistance.

 

[Every Time Ref]

This thread got weird. I've learnt a couple of reasonably interesting things about aerodynamics, a tiny bit I kind of already knew about the laws of rugby, and that Tigs Man can't form a decent analogy. An all round education it was, keep up the good work chaps.

 

[Ragey Erasmus]

Friction involves 2 or more mediums moving past each other, air resistance is that plus the head on impact of compressing the air in front of an object.

 

[Duck a l'Orange]

Friction involves 2 or more mediums moving past each other, air resistance is that plus the head on impact of compressing the air in front of an object.

Surely that can be assumed to be negligible in the case of a flying rugby ball?

Compression is only anything more than negligibly relevant if something is pushing to compress the air from the other side. In an unconfined sky there's not much.

My take on it- standing by to be corrected.

 

[LeinsterMan (NotTigsMan)]

This thread got weird. I've learnt a couple of reasonably interesting things about aerodynamics, a tiny bit I kind of already knew about the laws of rugby, and that Tigs Man can't form a decent analogy. An all round education it was, keep up the good work chaps.

I know analogies, I have the best analogies.

 

[Pieter Steph du Teague]

Why are we arguing about what friction is, has this argument really gotten that in depth and petty? From an English perspective I thought the pass was fine, although of course at the time I was yelling otherwise.