A friend (not Andy) was telling me about this (NRL) Footy Show segment. In it El Masri (who has recently announced his retirement, probably because of this GAGR Exposé [he’s a time traveller]) kicks a regulation (NRL, coke zero) ball inflated with helium over soccer goals from a supposed 100 metres distance. Of course i did not believe him because i have seen it busted twice on mythbusters (once with a throwing machine and then revisited with a kicking [punting] machine).
But then I started searching online video thinking it was a footy show joke where he’d kick it to Reg Regan who’d carry it the rest of the way and dunk it over the crossbar at the other end and then start jerking off. And my friend was having a laugh getting me revved up about a joke.Having found the video there seems to be no joke, they all seem to be legitimate? Check it out:
Looking at the video made me question whether this was actually possible, could mythbusters be wrong and the footyshow be right?
It made me look up wikipedia for some ball dimentions and subsequetly crush some numbers mathematically.
According to http://en.wikipedia.org/wiki/Football_(ball)
A rugby ball weighs about 400 grams (makes it a bit easier, could be more or less apparently)
Figure the total volume is max 3 liters I cant imagine drilling a hole in one and filling it up with more than 3 litres of water. (the more volume the more effect, if any, helium will have)
The density of air is 1.2 g/L at STP (standard conditions for temperature and [atmospheric] pressure)
The density of helium is about 0.18 g/L at STP.
Ball is inflated to 10 PSI (pounds per sqaure inch, according to wikipedia) or 68.75 kPa. Which is almost an extra 1 ATM, taking our atmosphere and the extra in the ball to almost 2 ATM (atmopsheric pressure).
Thus making the mass of air an air filled rugby ball is about 1.2 x 2 x 3 = 7.2 grams
and the mass of helium in a helium filled rugby ball about 0.18 x 2 x 3 = 1.08 grams
making total mass rugby ball plus air is about 407g.
and total mass rugby ball plus helium is about 401g.
So according to my calcs the difference is 6 grams…
probably the same amount of difference with a wet and dry ball. (thats why the hookers dry it first…)
Mythbusters came to the same conclusion as I about it being lighter but they also pointed out that due to it being slightly lighter it was more suceptable to wind resistance and their results actually showed the heluim filled ball travelling less distance. They said the initial velocity on the ball was the same with the kicking and throwing machines they used and the helium ball lost the momentum faster.
I’m still open with this debate It wouldn’t suprise me if the helium filled ball did go further, but not as much as hazem and the footy show made out.
Also the Wiki Football (ball) page also got me thinking if the rugby (union) balls are slightly heavier that might be why all our drop outs aren’t pathetic and go more than 30 metres. It doesn’t explain why the leagies only get 10 metres on a penalty kick to touch though (seems like a waste to me).
Is there anything i’ve missed?
What are your thoughts?
ps. Gagger, its still deleating any embedding html i add from youtube.