THANKYOU - now shut it Stevo

[heydude]

Schalk Brits... posted:
:eusa17:
Give up Rob I have !

sorry but i am only putting an opinion across about making a rule simple and not complicating it but if you want to be snotty about it sorry i said it then.

[willie c]

well said heydude some people get stressed out over nowt

[GeoffN]

heydude posted:

robjoenz posted:

heydude posted:
one why are you playing rugby in a car could be dangerous lol and two in layman terms if you threw it backwards you wouldn't need the rule simple really.

When you throw the ball backwards there are two things that affect the speed of the ball:

If a player runs at 10 mph and throws the ball backwards at 4 mph the ball will travel forward at 6 mph (10-4). It wouldn't be a forward pass though. Not as simple as you think!

sorry rob but now you are trying to complicate things and put mathamatics into a simple thing just pass the ball backwards and it is that easy how do you think they went on before the rule it must have been chaos.

It can't be made that simple, otherwise a player would have to stop running forward before he passed!
For the third time this year, I find myself agreeing with Rob!

[robjoenz]

heydude posted:
sorry rob but now you are trying to complicate things and put mathamatics into a simple thing just pass the ball backwards and it is that easy how do you think they went on before the rule it must have been chaos.

I could have explained in terms of actual momentum (mass of the ball multiplied by its velocity), that would have probably been over complicated.

The point everyone is trying to put across to you is that you can throw a ball back and it may still appear to go forwards.

The rule is needed more now because the game is a lot quicker than it used to be, so in the past although the rule prohibiting forward passing was more simple to employ.

[robjoenz]

Schalk Brits... posted:

S=UT + 1/2ATsquared eh Rob?

On similar lines yes. If the player is running at 1 m/s and passes it flat the forward moving acceleration would be zero simplfying to

S=UT

If the pass was in motion for one second the distance the ball would travel forward would be 1 m.

[GeoffN]

robjoenz posted:

Schalk Brits... posted:

S=UT + 1/2ATsquared eh Rob?

On similar lines yes. If the player is running at 1 m/s and passes it flat the forward moving acceleration would be zero simplfying to

S=UT

If the pass was in motion for one second the distance the ball would travel forward would be 1 m.

But that's still not momentum....which would be
1/2 MVsquared

not sure what the mass of a rugby ball is, though....
Also, we haven't taken any wind velocity into account...if a pass is sent forward at 1 m/sec, but into a 2m/sec headwind, would that still be a forward pass?
If the pitch was sloping, we would also have to compute the horizontal component of the vectors, unless the rule specifies "parallel to the pitch" rather than horizontally.

easy, really!

[robjoenz]

pie eaters posted:
im completely lost i hope ur joking with that equation

Nope, that's a very simple equation. It's gets complicated when you do integration and differential equations. Glad I'm out of education!

[robjoenz]

GeoffN posted:
But that's still not momentum....which would be
1/2 MVsquared

not sure what the mass of a rugby ball is, though....
Also, we haven't taken any wind velocity into account...if a pass is sent forward at 1 m/sec, but into a 2m/sec headwind, would that still be a forward pass?
If the pitch was sloping, we would also have to compute the horizontal component of the vectors, unless the rule specifies "parallel to the pitch" rather than horizontally.

easy, really!

No, no, no. Momentum is mass times velocity. The kinetic energy of the ball is 0.5 m v^2 !

The above equation tells you the distance relative to the ground that the ball travels so is relevant even though it is not the momentum rule.

On the latter point. Yes it would still be a forward pass, if the ball is thrown forward the point at which there is maximum acceleration is when the ball is just released. So a fraction after it is released the ball will have travelled forwards. Use the above equation for 's.'

[robjoenz]

pie eaters posted:
ok well its to early for me and i think u areall taking the mick

No mate, all very true and exciting!

[robjoenz]

pie eaters posted:
no i aint having it i aint gullible unlike some people i know theres no way anyone would know it or want to know it

haha, believe it or not some people actually use equations and stuff like this for work!

Have you not done Physics in school?