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maneius
I was just wondering how much of a shockwave would be produced by a 150lb person traveling at v. high speeds (such as the speed you reach when falling from the top of the big Ares skyscraper after being drop-kicked by the uber-adept spin.gif )
Nikoli
Depends, is the falling body awake?
Are they attempting to controle their fall?
maneius
Let's say unconcious, to make it a bit simpler.
Nikoli
How many meters up is the fall from? (I don't know the number of stories, nor the 2064 building code specs for meters per floor.
Phaeton
This whole thread reeks in so many ways of "Things You Don't Want to Hear While On a Run"...

In an amusing way, of course. biggrin.gif
Nikoli
biggrin.gif
Phaeton
Anyone ever played soccer with a small, semi-spheroid drone in-game before?

And furthermore, imagine this---converting the characters from Shaolin Soccer to SR.

ork.gif vegm.gif
Cray74
QUOTE (maneius)
I was just wondering how much of a shockwave would be produced by a 150lb person traveling at v. high speeds (such as the speed you reach when falling from the top of the big Ares skyscraper after being drop-kicked by the uber-adept spin.gif )

No shockwave to speak of. The top speed the body will reach in a minimum drag configuration (head down, limbs tucked in) is about 250mph. Nice splat, no shockwave.

In a maximum drag configuration (belly down, limbs spread eagled), the person will reach 120mph, give or take. Maybe some splat, but again, no shockwave.

Most objects have a terminal velocity (top falling speed in the atmosphere without power assist) of 300mph or less. Only planes or aerodynamic shapes get faster without power assist, and it's possible to go faster in the higher, thinner atmosphere (where falling humans have brushed mach 1 in, IIRC, the USAF "Man High" project).

Incidentally, assuming no drag, it would take a 637m fall to reach that 250mph top (normal) human speed, or about 2100ft. With drag, somewhat longer, perhaps closer to a kilometer/3000ft.
mcb
Terminal Velocity for the average person is between 90-120mph.

It depending a lot on what they're wearing how heavy and what position they're in while falling.

It should take 6-7 second to reach terminal velocity.

It should take about 600 ft of falling to reach terminal velocity.

mcb
Oddfellow
Pretty much nothing. It doesn't matter how tall the buliding is. Terminal velocity (the speed at which air resistance cancels out the force of gravity and you stop accelerating) is way less than the speed of sound (about 150 mph vs. 780 mph on a warm summer day). If you were on the ground all you would feel is a little wind, and then splat! The person isnt going much faster than a really good tennis serve. On a related note, pennies thrown off skyscrapers don't make craters or kill anyone. OF course, the beauty of RPGs is that you dont actually have to follow physics (see, for example, magic). So feel free to make pennies deadly or give bodies as big a shockwave as you want.

Edit: Beat to the punch
Kagetenshi
Anyone have any tips for minimizing falling speed using ordinary carried or easily portable materials?

~J
Dice
Assuming a terminal velocity of ~120mph is reached then that equates to ~55m/s. 150lbs is roughly 70kg

0.5*70*(55^2) = 105875 Joules of kinetic energy goes into the impact.

1g of TNT is about 4000J...

So the impact of a falling unconcious human is about the same total energy release as 26 grams of TNT (1 ounce).

A lot of that enery will be absorbed into the remains of the body as it does work breaking bones etc.

Basically, unless the body actually lands on you, you would probably not feel any appreciable force if you were standing more than a few feet away from it. You might get blood and brains splattered all over your clothes though...
JaronK
Parachute? I know they've developed a funny wing looking thing, like a bat's wing, where the fabric is spread from the cuffs of the sleaves to the lower chest, something like a flying squirrel actually. They did it in Laura Croft II. Doesn't stop the fall, but should allow some controll and slow you a bit.

Now, one thing to consider is that the terminal velocity of a heavily cybered troll might be very high. We know that Titanium Bone Lacing adds quite a bit, and maybe the other parts would too... the increased density would likely lead to much faster speeds. Still not enough for a shock wave though... but a shockwave might make a very nice adept power.

JaronK
PBTHHHHT
QUOTE (Kagetenshi)
Anyone have any tips for minimizing falling speed using ordinary carried or easily portable materials?

blech, that post alone is worth the "Things You Don't Want to Hear While On a Run..."

Question is... can you macguyver those items together in the given time span to help slow your fall down? hehehe...

I think the main question now is instead of shockwave (which has been proven won't happen) of how large of a splatter you'll make on the ground below.... eek.gif
RedmondLarry
Petite female nannies can be carried aloft by an open umbrella.
Raygun
You'd have to fall a long way to develop a shock wave with your body.
Mystical_X
QUOTE
Now, one thing to consider is that the terminal velocity of a heavily cybered troll might be very high. We know that Titanium Bone Lacing adds quite a bit, and maybe the other parts would too... the increased density would likely lead to much faster speeds


Sorry, but i think that Mr. Newton proved that just because something is heavier does not mean that it falls any faster. Go get a hammer and a soda can and drop them at the same time and see which hits the ground first.
Dice
QUOTE (Mystical_X @ Jun 21 2004, 10:18 PM)
Sorry, but i think that Mr. Newton proved that just because something is heavier does not mean that it falls any faster. Go get a hammer and a soda can and drop them at the same time and see which hits the ground first.


'Twas Galileo that showed things fall at equal rate independent of mass (excluding air resistance).

Newton explained it, but Galileo was first to demonstrate it.
Mystical_X
QUOTE
'Twas Galileo that showed things fall at equal rate independent of mass (excluding air resistance).

Newton explained it, but Galileo was first to demonstrate it.


thanks, I always get them mixed up.
Cray74
QUOTE (Mystical_X)
QUOTE
Now, one thing to consider is that the terminal velocity of a heavily cybered troll might be very high. We know that Titanium Bone Lacing adds quite a bit, and maybe the other parts would too... the increased density would likely lead to much faster speeds


Sorry, but i think that Mr. Newton proved that just because something is heavier does not mean that it falls any faster. Go get a hammer and a soda can and drop them at the same time and see which hits the ground first.

Actually, that theory only works in a drag-free environment. On the moon, free of air, a hammer and feather fall at the same rate.

On Earth, thick with air, a hammer and feather fall at very different rates.

Likewise, a titanium-BL troll would probably fall faster than a human, owing to much greater mass, reduced by somewhat greater surface area.

Tandem parachutists (like Bush Sr. recently) have to deploy drag chutes to keep their fall rate to 120mph. With twice the rate and only slightly greater frontal area, they can reach 200mph and higher without that small chute slowing them down.
Dice
QUOTE (Cray74)
QUOTE (Mystical_X @ Jun 21 2004, 10:18 PM)
QUOTE
Now, one thing to consider is that the terminal velocity of a heavily cybered troll might be very high. We know that Titanium Bone Lacing adds quite a bit, and maybe the other parts would too... the increased density would likely lead to much faster speeds


Sorry, but i think that Mr. Newton proved that just because something is heavier does not mean that it falls any faster. Go get a hammer and a soda can and drop them at the same time and see which hits the ground first.

Actually, that theory only works in a drag-free environment. On the moon, free of air, a hammer and feather fall at the same rate.

On Earth, thick with air, a hammer and feather fall at very different rates.

Likewise, a titanium-BL troll would probably fall faster than a human, owing to much greater mass, reduced by somewhat greater surface area.

Tandem parachutists (like Bush Sr. recently) have to deploy drag chutes to keep their fall rate to 120mph. With twice the rate and only slightly greater frontal area, they can reach 200mph and higher without that small chute slowing them down.

Given that terminal velocity is proportional to the square root of (weight/surface area), and that area increases by the square and weight by the cube (assuming constant density), them a troll will be have a terminal velocity about 41% higher than a human (root 2... Troll about twice the height therefore 4 times the area and 8 times the mass... 8/4 = 2).

Thios will double the KE velocity compnent (root 2 squared...) and be 8 times the mass component, for a total KE 16 times greater... so 1lb of TNT....

Most of the energy will still go into pulping the body rather than creating a shockwave... but I'd like to be about 4 times further away from the impact to avoid the splatter.

Oh yes, bear in mind when equating energies to x amount of TNT that the TNT releases its energy in thousands or ten-thousandths of a second, whereas a body impact will release the energy over hundredths of a second (so a good 10-100 times less peak energy output)

BTW and just for giggles, the 100kJ for the human impact would raise the temperature of the water content in the body (assuming 70% water) by a mere 0.5C, even if *all* the energy just went into heating up the mess. For the troll (assuming similar ratio of water content) it would rise 1C (16 times the energy, 8 times the mass of water, thus twice the temperature increase).

Most of the energy will be dissipated by various elastic collisions within the body as it decelerates, breaking bones, heating up the body (a tiny bit), heating up the ground (even less) denting the sidewalk, splattering blood and other mushy bits around within a few feet of the impact, making a sickening 'crump' noise, and finally producing a shockwave that would be no stronger (in all likelyhood) than a single sturdy waft from a large old-fasioned ladies fan.

You might feel a brief gust of air if you are within a few feet, but there will not be windows across the street shattering or car alarms going off (unless the body landed on the car in question... which would crumple and absorb more energy so even less shockwave then...)
theartthief
Does anyone else find it odd that we are discussing the physics behind a being falling to its death from high places? eek.gif

- theartthief
Raife
Shockwave is caused by the amount of force hitting the ground. So a person falling from that hieght wont make much of a wave, but he would screw up a car, and probably consider the day "ruined" for purposes of "fun". I would hazard a guess that a person falling from that hieght would rate the entire day based on that event, rather than say... the really good breakfast he had.

For reference Brinks armored cars are capable of withstanding a 500lbs 9square feet load dropped from a hieght of 500 feet.

If your looking for "matrix" style shockwave you MIGHT see a little wave action in the safety glass of a car if you slowed the camera way down.
Kagetenshi
QUOTE (theartthief)
Does anyone else find it odd that we are discussing the physics behind a being falling to its death from high places? eek.gif

Why would that be odd?

~J
theartthief
QUOTE (Kagetenshi)
QUOTE (theartthief @ Jun 21 2004, 11:44 PM)
Does anyone else find it odd that we are discussing the physics behind a being falling to its death from high places?  eek.gif

Why would that be odd?

~J

Oh, I don't know....

"Sarah, I'm telling you the guy would go splat. I don't care what you say.... oh yeah, Bob, pass me the popcorn."

- theartthief
SirBedevere
You could slow your fall (a bit) by opening your jacket and holding the edges to increase your drag. You might have a better chance of surviving, but I suspect that all that would happen is you would have longer on the way down to think about the splat. biggrin.gif
Abstruse
You wouldn't slow down that much. The fabric of almost any jacket would rip from the force if it weren't just jerked out of your grip. The shockwave wouldn't be much at all (still there, but just so small it has no effect on anything), but the mass of the object impacting would make a difference when it hits, possibly shaking the ground depending what he lands on and what chrome he's got in him. Might set off a car alarm at 3m or so...

Then again, I've always been a fan of "screw realism" when the cinematic way is more fun nyahnyah.gif

The Abstruse One
Nikoli
From what I understand, the best chance to survive a fall like that is go spread eagle and try your best to land flat on your back. Life will suck for a good long while, if you survive, but your chances are dramatically increased when you do.

Keep in mind, a friend of my family used to parachute as a hobby, his main and spare failed to open. He's alive, but the mind of a 12 yr old. Personally, I'd have opted for a cannon ball instead.
kevyn668
Your best chance to survive a fall barring parachutes?

1) Magic

2) Hand of God

Thats pretty much it. Have a nice day. smile.gif
Raygun
QUOTE (Raife)
Shockwave is caused by the amount of force hitting the ground.

No. The physical definition of "shock wave" is the phenomenon caused by a body moving through a medium faster than sound can travel through it. At the leading edge of said object, molecules build up upon each other, creating a compressional wave of large amplitude. The "sound barrier". That pressure is eventually released, which is the cause of what is most commonly known as "sonic boom".

What you're thinking of is pure CGI magic. Concrete and glass are not that flexible, even in slow motion. It will just shatter.
lspahn72
QUOTE (theartthief)
Does anyone else find it odd that we are discussing the physics behind a being falling to its death from high places? eek.gif

- theartthief

Not at all.. As a GM nothing is funnier then a free fall from a high window!!! As far as damage goes, its still : power= 1/2 meters fallen, and the letter is based on teh power number per the collision chart?

maneius
QUOTE (Cray74)

No shockwave to speak of. The top speed the body will reach in a minimum drag configuration (head down, limbs tucked in) is about 250mph. Nice splat, no shockwave.

In a maximum drag configuration (belly down, limbs spread eagled), the person will reach 120mph, give or take. Maybe some splat, but again, no shockwave.

Most objects have a terminal velocity (top falling speed in the atmosphere without power assist) of 300mph or less. Only planes or aerodynamic shapes get faster without power assist, and it's possible to go faster in the higher, thinner atmosphere (where falling humans have brushed mach 1 in, IIRC, the USAF "Man High" project).

Incidentally, assuming no drag, it would take a 637m fall to reach that 250mph top (normal) human speed, or about 2100ft. With drag, somewhat longer, perhaps closer to a kilometer/3000ft.

QUOTE
No shockwave to speak of. The top speed the body will reach in a minimum drag configuration (head down, limbs tucked in) is about 250mph. Nice splat, no shockwave.


Pity.
Okay...
What combination of cyber would best enable you to survive said fall with a minimum of injury (obviously there's going to be some, but, eh, thems the breaks).

Oh, by the way, replace the drone with a dwarf with his legs tucked under his armpits and a troll with a beefed up cyber leg, much more fun (and cliched).
maneius
sorry about the quote messup.
Nikoli
Well, titanium bone lacing and dermal sheathing 4, along with cyber-jacks at maximum rating might help.

then again you could just add a cybergun version of the line-launcher and avoid the sudden stop altogether
Kagetenshi
Spidertroll?

~J
GreatChicken
QUOTE
then again you could just add a cybergun version of the line-launcher and avoid the sudden stop altogether


That will still create a sudden stop on your hand, if it doesn't snap first. About the only thing that avoids sudden stop is a parachute.
Zazen
I think it's reasonable to say that the line-launcher has a brake which can squeeze the line gradually more and more, so that one can slow their descent without locking the line reel.
Cray74
QUOTE (GreatChicken)
That will still create a sudden stop on your hand, if it doesn't snap first. About the only thing that avoids sudden stop is a parachute.

If it works correctly. Chutes can have "hard openings" sometimes.

When I took my skydiving lessons many moons ago, one of my questions was "Did you ever know a skydiver to piss themselves in fear on their first jump?"

The answer was to the effect of, "No, but I knew a skydiver with 1200-odd jumps under his belt who had a hard opening and chose the wrong moment to fart. He had some cleaning and scraping to do when he landed." wink.gif

QUOTE
I think it's reasonable to say that the line-launcher has a brake which can squeeze the line gradually more and more, so that one can slow their descent without locking the line reel.

Sounds good to me.
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