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PDR
641718.  Sun Nov 29, 2009 9:44 am Reply with quote

It looked as fake as the moon landings.

PDR

 
Davini994
641735.  Sun Nov 29, 2009 10:23 am Reply with quote

Efros wrote:
Any theory based on a single piece of evidence is not a theory but a single observation.

No, it's a theory based on a single observation. Or to put it another way, one more than you've got. I'll also note that you haven't proposed an alternative theory for the observation.

Kicking it 100m isn't within normal variation. It isn't possible with a normal ball. In this situation discounting the evidence because it doesn't count as careful statistical analysis is preposterous. You have in fact reached the opposite conclusion apropos nothing. You need to at least propose an alternative explanation for the observation if you feel the conclusion to be erroneous.

 
PDR
641743.  Sun Nov 29, 2009 11:12 am Reply with quote

My alternative explanation involves the pressure pulse induced in the helium by the kick initiating a cold fission reaction in the helium.

PDR

 
Davini994
641756.  Sun Nov 29, 2009 11:47 am Reply with quote

Mmm, cold fish.

 
Sadurian Mike
641758.  Sun Nov 29, 2009 11:56 am Reply with quote

You'll not find any here.



'Cos it's a little otter.

 
PDR
641764.  Sun Nov 29, 2009 12:32 pm Reply with quote

Sadurian Mike wrote:
You'll not find any here.

'Cos it's a little otter.


GO TO YOUR ROOM!

PDR

 
Efros
641802.  Sun Nov 29, 2009 2:51 pm Reply with quote

Davini994 wrote:
Efros wrote:
Any theory based on a single piece of evidence is not a theory but a single observation.

No, it's a theory based on a single observation. Or to put it another way, one more than you've got. I'll also note that you haven't proposed an alternative theory for the observation.



A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing.

One of the many steps involved in the scientific method. I haven't proposed an alternative as the phenomenon hasn't been sufficiently tested to prove that it is reproducible.

 
Davini994
641815.  Sun Nov 29, 2009 3:06 pm Reply with quote

Not really, no. This is the relevant item from wiktionary:

Wiktionary wrote:
A coherent statement or set of statements that attempts to explain observed phenomena.

Or possibly this one:

Wiktionary wrote:
An expectation of what should happen, barring unforeseen circumstances.


http://en.wiktionary.org/wiki/theory

As I've repeated several times (get it?) repeated testing in various conditions is a good idea. But it doesn't mean that you can ignore evidence just because there's only evidence of it a few times, like on the vid.

You only need one asteroid to fall out of the sky to make the theory "sometimes asteroids fall out of the sky" true to a good level of confidence. Equally, or possibly even stronger, a video of Hatem Al Mazri apparently filling a rugby ball with helium then kicking it further than it's ever been kicked before, more than once, is good evidence for the theory filling a rugby ball with helium allows it to be kicked further.

Now, it might be the case that there's a problem with the evidence, but "it's only on the video once" isn't even remotely a refutation of it.

If you try and walk through patio doors and bounce off the glass because they are closed, do you try and walk through again?

 
Efros
641825.  Sun Nov 29, 2009 4:22 pm Reply with quote

Not going to carry this discussion any further, you obviously are much more experienced than I in the area of research and the application of the scientific method in the determination of a theory to explain a phenomenon.

 
Posital
641828.  Sun Nov 29, 2009 5:03 pm Reply with quote

Oooo - get you!

Not sure Dav was talking about scientific method - he was simply asking you to engage in hypothesis building, methinks.

Efros wrote:
One of the many steps involved in the scientific method. I haven't proposed an alternative as the phenomenon hasn't been sufficiently tested to prove that it is reproducible.
I guess you're worried about pons and fleishmann (sic).

Must say, if all other environmental factors have been taken into account (photoshop, tailwind, short measures, and lying), then there is something to be explained.

If the gas content on a tyre can reduce fuel consumption, then perhaps this is possible somehow.

I think there is quite a gap in our knowledge about how these systems operate in the real world.

PS: I still don't understand why plastic toy balls curve the opposite direction to official footballs when you put some spin on them when kicking.

 
Posital
641829.  Sun Nov 29, 2009 5:09 pm Reply with quote

I suspect it's something to do with the elasticity of the gas and the transfer of energy on kicking - probably nothing to do with the flight of the ball.

 
Spamperial
641837.  Sun Nov 29, 2009 6:43 pm Reply with quote

I'd be interested to see the opposite case tested whereby they fill the ball with a particularly heavy gas and see if that shortens the kicks.

How much do you think it would cost to borrow Jonny Wilkinson for an afternoon and let him rip on a bunch of identical looking balls filled with different gases? I won't be satisfied until it's done.

 
Efros
641842.  Sun Nov 29, 2009 7:34 pm Reply with quote

Posital wrote:
Oooo - get you!


Yeah get me!

Posital wrote:
Not sure Dav was talking about scientific method - he was simply asking you to engage in hypothesis building, methinks.

Efros wrote:
One of the many steps involved in the scientific method. I haven't proposed an alternative as the phenomenon hasn't been sufficiently tested to prove that it is reproducible.


I guess you're worried about pons and fleishmann (sic).


Nope they can worry about themselves.

Posital wrote:
If the gas content on a tyre can reduce fuel consumption, then perhaps this is possible somehow.


Reduction in tyre pressure produces increased contact of the tyre with the road, so more friction so less miles per gallon

Posital wrote:
PS: I still don't understand why plastic toy balls curve the opposite direction to official footballs when you put some spin on them when kicking.


Can't help you there my ball kicking days were over some 20 odd years ago. Possibly some kind of air resistance effect, who knows.

 
Sadurian Mike
641896.  Mon Nov 30, 2009 5:45 am Reply with quote

It occurred to me last night that the reason the ball might fly further has nothing to do with its inertial mass or the velocity at which it is kicked.

Quite simply, if it is filled with helium it is going to stay aloft for longer because it is lighter and thus gravity doesn't pull it down as quickly. If it stays up longer then it will fly further than an equivalent ball kicked with the same velocity, just because it hasn't hit the ground and lost its forward momentum.

This may have been covered but I probably skipped it whilst my brain was on auto-pilot.

 
PDR
641904.  Mon Nov 30, 2009 6:44 am Reply with quote

Sadurian Mike wrote:

Quite simply, if it is filled with helium it is going to stay aloft for longer because it is lighter and thus gravity doesn't pull it down as quickly.


KLAXON!!!

Objects will fall at the same rate regardless of their weight - a chap called Galileo demonstrated this by dropping things from a pizza hut.

IF there is a difference it will be due to mass/drag ratios (affecting the deceleration) or different elasticities (affecting the energy transfer from boot to ball).

PDR

 

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