Plane on a treadmill question

Soldato
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Slightly less forces involved than 100mph to full stop then :D.

Majority of injuries are caused by trying to break a fall iirc. Being drunk can prevent you from successfully breaking your fall (or even trying) so would reduce the injuries.

Never really understood why the brains natural reaction to falling is to stick your arms out and break a wrist whereas if you just hit the floor chances are you'd hurt yourself less.

I don't think I've ever had more than a bruise when drunk but I've had numerous broken bones when sober :confused:. Thus being drunk is good for me :D.
But
A greater chance of medium injury by sticking your arms out reduces the risk of major injury.
 
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Slightly less forces involved than 100mph to full stop then :D.

Majority of injuries are caused by trying to break a fall iirc. Being drunk can prevent you from successfully breaking your fall (or even trying) so would reduce the injuries.

Never really understood why the brains natural reaction to falling is to stick your arms out and break a wrist whereas if you just hit the floor chances are you'd hurt yourself less.

I don't think I've ever had more than a bruise when drunk but I've had numerous broken bones when sober :confused:. Thus being drunk is good for me :D.

Velocity + Beer = LOLz (Real equation)
 
Sgarrista
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If you're in a lift with the doors open and it plummets to the ground, can you jump upwards and out at the second of impact and survive? :D

Only if you can jump upwards at the same speed the lift is falling.

If its falling at 100mph and you jump up at 5mph, youre still going a net 95mph down.... meaning a nice owwie at the bottom.
 
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(totally spell wrong) prptectors in your gloves.

A small ceramic/plastic slider on the pad of your palm at the base of your thumb.

When you put your hand down to catch yourself by instinct the huge fkrces snap your wrist as it sticks tk the floor.

The slider makes the palm slide away snd you just splat down and slide along safety (well safe inside your leathers without the leathers you slide to a grisly death)

Sounds like what skaters have on protective gloves and what I've worn when Ice skating. Definitely seems to work - instinct is to spread arms and hands which will break something!
 
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I've just been watching a Jackie Chan movie where they jump from a train onto grass.
If the train is moving at 100mph would they hit the ground at 100mph and therefore kill or maim themselves?
My 1 brain cell says that would happen.

Depends how well they are able to skid/roll on the surface they land on. They won't hit the ground "at 100mph" in the sense of a 100mph impact as their vertical velocity won't be anywhere near that high. As long as they're able to lose the kinetic energy across a long period of time they'll be fine, barring a potential loss of skin depending on what clothes they were wearing.

Think of motorbike riders who crash at 150-200mph but come out relatively unscathed.
 
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Depends how well they are able to skid/roll on the surface they land on. They won't hit the ground "at 100mph" in the sense of a 100mph impact as their vertical velocity won't be anywhere near that high. As long as they're able to lose the kinetic energy across a long period of time they'll be fine, barring a potential loss of skin depending on what clothes they were wearing.

Think of motorbike riders who crash at 150-200mph but come out relatively unscathed.

Yes but those motorbike riders have leathers and varipus ceramic and kevlar reinforced fabrics, airbags, shock absorbing armour and helmets

You arent talking a potential of skin you are talking about loosing inches deep of skin, fat, muscle and bone not to mention severe burns.
 
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That explains it better than anything can, if that was doing 100mph he'd be dead or very seriously injured.

I suppose it's just another one of those Hollywood myths where 100s if not 1000s of films have featured somebody jumping from a moving vehicle unscathed.

I've seen quite a few films where they jump out onto water, in real life I presume that would be nearly as bad?
 
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I must have just watched that about 20 times now. Can't tell if he's trying to get off as the train has just left (wrong train), or if he's trying to get off early (impatient).

That explains it better than anything can, if that was doing 100mph he'd be dead or very seriously injured.

I suppose it's just another one of those Hollywood myths where 100s if not 1000s of films have featured somebody jumping from a moving vehicle unscathed.

I've seen quite a few films where they jump out onto water, in real life I presume that would be nearly as bad?

I suspect water is a little easier compared to solid land, i guess it all depends on the angle that you've jumped into the water. If you come off the train horizontal then you'd probably skim across the water (think rock skimming) until you've lost momentum. However coming off vertically would probably be similar to opening your parachute too late - hitting the water at high speeds could potentially break your legs.
 
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Maybe if you could somehow get the mattress parallel to the ground as you fell with the leading edge pulled upwards a bit (like a toboggan) to encourage sliding... But I'm oretty sure the mattress would stick and you would be catapulted forwards in a high-velocity somersault. Not nice.

If I were to leap from a moving train at speed I think rather than something soft I would want something extremely hard and smooth underneath me - like a large metal tray. Still wouldn't rate my chances though given British train fares, I can see why one might try it.
 
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I thought water was as solid as concrete past a certain height like 30 metres or so.

No, it isn't. Liquid water is liquid regardless of how far you fall into it.

That wouldn't be much help to your shattered corpse, though. Falling into a practically incompressible liquid won't be as bad as falling into concrete, but it'll do more than enough damage to kill you with great overkill. If you hit water at enough speed, even going in feet first perpendicular to the surface won't be enough to save you even if the water is deep enough for you to stop before you rammed into whatever is at the bottom of the water. But liquid water isn't solid.

Back to the OP...a person could survive hitting grass with a velocity of a bit under 100mph parallel to the grass if it was soft ground under the grass with no rocks and it was a slope and they were wearing enough protection for them to be able to slide a long way and they landed correctly so they did slide rather than windmill and bounce. People have come off bikes at that sort of speed and survived with healable injuries.

EDIT: Anyway, it was Jackie Chan. So he probably did it for real, like he usually does.
 
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Caporegime
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No, it isn't. Liquid water is liquid regardless of how far you fall into it.

That wouldn't be much help to your shattered corpse, though. Falling into a practically incompressible liquid won't be as bad as falling into concrete, but it'll do more than enough damage to kill you with great overkill. If you hit water at enough speed, even going in feet first perpendicular to the surface won't be enough to save you even if the water is deep enough for you to stop before you rammed into whatever is at the bottom of the water. But liquid water isn't solid.

Back to the OP...a person could survive hitting grass with a velocity of a bit under 100mph parallel to the grass if it was soft ground under the grass with no rocks and it was a slope and they were wearing enough protection for them to be able to slide a long way and they landed correctly so they did slide rather than windmill and bounce. People have come off bikes at that sort of speed and survived with healable injuries.

EDIT: Anyway, it was Jackie Chan. So he probably did it for real, like he usually does.

I dont think he meant it was solid but that the resultant G force was the same.

Which i think in one muthbuster episode theg did that.

Droped the dummy on concrete and water and the difference in impact force was negligible.


Water just cant move out of the way to slow the duration of impact much
 
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Physics always made my mind explode. Never could get it.

I lost interest at school when we did a 'tiker tape' exercise involving pushing a minature car down a slope. My primitive brain just didnt get it.

I am the sort of guy that cant explain how a boat works, although I obviously know that it does.
 
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