2 Story Fall Death, Realistic?

[KappaWing]

I was watching this movie where this guy fell two stories, landed on his head in the pavement, and instantly died. How realistic is this? It seems like someone would need to fall much further.

[Klaynos]

Onto his head, yep would think that'd kill you...

[DrDNA]

d = assuming that a 2 story building is about 20 ft or approx 6 meters tall.

a = accel due to gravity = approx 10 m/s

a =v/t; v= at; and d = 1/2 at^2

so t = (sq root of (2 x 6 meters)/10 m/s^2)

the guy would fall for about 1.2 sec.

v = 10 m/s^2 x 1.2 s

that's about 12 meters/sec

converting meters back to feet to miles......

I say that he would hit the ground at about 24 mph with the whole force of his body behind him......about 160 lbs on average.

Probably didn't feel a thing....

But I haven't had general physics in a LONG LONG time so you might want to check my math........

[iNow]

You forgot to multiply his weight by his speed... the force is much greater, and it doesn't take much to snap a neck or crack a skull.

[DrDNA]

Uhmmmm....Well, I stated that the force of the impact would include the whole weight of his body (about 160 lbs). I didn't want to convert lbs, to kg to Newtons, etc....and everybody knows F = ma

 

Man, you grade tough!

 

Don't I get partial credit?

 

Is this going to be on the test?

 

[iNow]

....and everybody knows F = ma

 

What'd you just say about my mother!

[ecoli]

this thread is sort of ironic, if you think about it. Most of the garbage that comes out of hollywood these days is people surviving high speed crashes, the car flips over three times, falls down a cliff and the character walks out with a manly scratch on his face and hair neatly combed.

 

We used to ask is feats like this are likely. Now, we accept the incredible as the norm and the real as unlikely. It's funny how the media influences our perceptions of reality.

[NeonBlack]

Dr. DNA, it sounds stupid to say this, but it wasn't the fall that killed him, but the landing.

What I mean is that at the end of a Geronimo (or any impact), pressure is more important that velocity. The way you land determines the pressure.

When falling, you will acquire some momentum. When you land, the shorter the impact time is, the greater the force will be. This is why getting hit with a golf ball will hurt much more than getting hit with a pillow, even if they weigh the same and are going the same speed.

The second thing is that if the force is distributed over a small area, the pressure will be greater. Consider the difference between standing on the floor and standing on a nail. The downward force is the same in both cases, but for the nail, the force is over the small point of the nail rather than the entire sole of the foot.

 

So, your head is pretty hard and the cross section of your spine is pretty small.

I imagine that it would be possible to break your neck even after falling from a fairly small height.

[Glider]

An interesting statistic is that four stories high seems to be the cutoff point for fatality.

 

An odd fact is that in suicide by jumping, most people lack the courage to jump from higher than the fourth story of a building and by coincidence that height is just below what would be more certain to kill you.

 

At the height of four stories (from which most jumping suicides are attempted), you are likely get smashed calcaniums, punctured acetabulums (where the head of the femur is pushed through), splayed pelvis and compression injuries to the spine, but rarely immediate death.

 

At heights above four stories, death is much more certain, but many fewer people jump from such heights.

 

(note that nothing is certain, you could die from hitting your head after tripping on the pavement, but it's not likely).

[Severian]

You can fall out of a plane and survive. You can fall off a step ladder and die. It all depends on individual circumstance.

 

My brother fell off a sixth floor balcony on holiday once, landing on the marble floor beneath. He walked away (though admitedly straight to a hospital). I suspect what saved him was that he hit the balcony on every floor he passed on the way down.

[insane_alien]

if your body is there to act as a shock absorber, you can survive. if you are trained to be able to land well, you jump from that height and walk away(like how you get trained for parachute jumps) i could probably manage it but i wouldn't want to jump off 2 stories to give it a shot, i like my bones intact. but if you land on your head then get slammed by your body, your not going to be very well at all.

[Phi for All]

Elastic deformation doesn't work well on the human skull.

My brother fell off a sixth floor balcony on holiday once, landing on the marble floor beneath. He walked away (though admitedly straight to a hospital). I suspect what saved him was that he hit the balcony on every floor he passed on the way down.

I think I met your brother, albeit briefly. Nice chap, in a bit of a hurry. My wife and I were staying on the third floor.

 

He didn't have much regard for the niceties like personal space. Rather clingy if you ask me.

 

Tell him they charged me for the robe.

[D H]

One significant cause of death (particularly among the elderly) is slipping in the shower. Death occurs when the head hits the hard wall or tub, often breaking the neck. This slip in the tub is much less than a two story fall.

 

Bicycle accidents (particularly endos) often result in a direct collision between the head and the pavement. 24 mph is a good pace on a bicycle. A 24 mph collision in which the head absorbs the full impact of the collision is deadly. Those helmets save lives. (Mine, for example.)

[John Cuthber]

Imagine I got a hammer that weighed about as much as a person , say 140 pounds, and I lifted it 2 storeys up then dropped it on someone's head.

 

It's not surprising the guy died.

 

(and I'm not sure a cycle helmet would have saved him)

[insane_alien]

well, maybe if you have a big spring attached to the top. gotta think outside the box dude.

[Phi for All]

well, maybe if you have a big spring attached to the top. gotta think outside the box dude.

Is that the box marked ACME, Mr. Coyote?

[insane_alien]

yep. i also got a HUGE firework style rocket with it. that roadrunner is MINE.

[KappaWing]

So if the cutoff point is four stories for landing on your feet, what would be the cutoff point for landing on your head?

 

BTW this one guy jumped five stories and survived, but was paralyzed.

 

"It also features the final drum performance from Carl-Michael Eide (Czral), who is now paralyzed from the ankles down after an all too unclear accident in which he fell from the fifth floor of a building."

Link

[iNow]

So if the cutoff point is four stories for landing on your feet, what would be the cutoff point for landing on your head?

If I were to hold you up by your ankles, and drop your head on to concrete, it probably would kill you at about a foot or two off the ground.

[alan2here]

Id say 1 story would be ample