surviving a falling lift

[kellyrazor]

if a broken lift was falling from around the 20th floor and you were to jump at the very last second before the lift hit the bottom would you beable to survive?

[Phil7]

Maybe - It does help to be out of contact with the floor when it hits, it prevents the bones shattering from the shock wave.

However, you then have to land, and break mutiple bones and still probably die - don't try it at home. :0)

[Quizmonster]

Click here and you will be linked to an AnswerBank archive page where there are 11 instances of this question recorded. Just click on each of the red headings to see what replies were provided.

[Iggle Piggle]

How do you know when the lift is about to land???
theoreticaly the answer is yes but the benefit would be marginal, you might cheat death but would still be carried out like a rag doll.
Any help ?

[villa_fan007]

thinking about this you would prob bang your head quite hard on the lift roof. so maybe just take the stairs from now on

[Quizmonster]

Oh dear! Click here for a physicist's answer.

[brachiopod]

Your chances of survival would be about the same as quickly jumping into the back seat of your car as you are about to hit a concrete wall at 80mph.

[PhilLew]

If you were inside a falling lift you and the lift would both be in free fall, so you would effectively be weight-less relative to the lift. When the lift hit the bottom and stopped, you would keep going at the free fall speed untill you hit the floor of the lift just the same as if you were falling in an empty lift shaft.

[ll_billym]

Of course you would survive.

The average human jumps up at about 61mph (for the first few inches anyway). The average broken lift falls at around 67mph after 20 average storeys.

If you time your jump just right then you will be able to launch yourself from the floor of the lift at sufficent speed to turn your 67mph descent into a 6mph descent!!!

This equates to an average jump off an average 5 feet high wall, which may jar your knee joints slightly but you will certainly live to laugh at the remains of your less educated lift passengers as they lie bloody and lifeless, splattered and scattered around your slightly sore feet.

Think about it.

[nightmare]

Oh dear, oh dear,oh dear !

Ignore all the answers thus far, and think of it like this:
you have just fallen from then 20th floor (in a lift).
If you stay in the lift, you will be a bloody mess on the lift floor when it hits the ground.
If you step outside the lift, you are still faling at the same speed and will therefore become a bloody mess on the ground.
In order to survive, you must decrease your rate of descent to a survivable value, but this means decelerating. You need to find a way of providing an upwards force, acting over sufficient time not to injure yourself.
The ground provides the force necessary to stop your descent, but the time is too short - the deceleration is too high.

[Phil7]

Oi, don't ignore the first answer. It was quite carefully phrased and hitherto no-one has disputed it, as opposed to the dubious question of decreasing your velocity by jumping!

[Quizmonster]

And don't ignore my two answers either! Both provide links with indisputable scientific data proving that one has no prospect of being able to jump in these circumstances.

[ll_billym]

Well I don't see why my answer should be ignored either as it is much easier to follow and makes more sense on the face of it than the so-called "scientific" answers.

[Quizmonster]

I'll make this my last effort! Click " target="_blank">http://www.straightdope.com/classics/a1_205a.h tml"> here to reach the Straightdope web-page on the matter. It's not very scientific but it is crystal clear on the situation re jumping off the floor of a falling lift...and in the plainest of language! Basically, it says, "You can kiss your a$$ goodbye." Pretty straightforward, eh?

[Quizmonster]

Click here. Sorry for the messed-up link earlier.

[wildwood]

You can minimise you injuries by lying on your back on the floor of the lift and put your jacket under your head.

An even better idea would be to shout "everybody lie on the floor" and then lie on top of your fellow pasengers and use them as a mattress lol.

[jollygreen]

Pretty sure Mythbusters tried this one and decided it was a complete fallacy...

[adam3132]

Big squishy pants!! They would break the impact..don't leave home without them ! Or...take the stairs!

[Phil7]

I'm sorry, ll_billym, but we should ignore your answer because the figures just don't add up.

A vertical jump with take-off velocity of 61 mph (90 f/s) gives half-flight time (v/g) of 2.8 sec., giving height of jump (0.5g.t^2) = 125 ft. !!!

A better set of numbers would be for a jump of 3 ft, say (from a standing start, don't forget). This gives half-flight time (Sqrt(2h/g)) of 0.43 sec., giving take-off velocity (g.t) = 14 f/s.

Compare this to your rather low estimate of 67 mph (98 f/s) for speed of lift and you should agree that it makes very little difference.
-----------------------------------------------------

[What your answer implies, is that by the time the lift is travelling at 61mph, you could jump back up to the floor you started at (give or take air resistance).]

[ll_billym]

LOL. If you notice the language in the last sentence of my answer you may gather that it was meant to be humorous rather than scientific. The correct answer had already been given by Quizmonster.

It just makes me laugh that such a simple scientific fact is so hard to explain in simple language and an answer like mine seems so easy to accept.

The plain english version is that you and a lift are falling very fast towards the ground at the same time. If you kick both your legs against the lift just before you both crash into the floor you will crash into the floor a split second after the lift does.

I still think my first answer was better.

[nightmare]

My apologies to Phil7 and Quizmonster