The Mystery of the Plummetting Lift

[Easy 10]

Cheers Daveyboy...here's the answer from that link:

"Sorry, kiddo. The only thing you can do if you get stuck in a falling elevator is tuck your head between your knees and kiss your arse good-bye. It's a simple matter of physics. Let's say, for purposes of illustration, that your falling elevator reaches a terminal velocity of 100 feet per second. Even if you manage a leap of Nureyevian proportions, you'll only reach a speed of maybe 5-10 feet per second. (For purposes of comparison, a sprinter doing 40 yards in five seconds is moving at 24 feet per second--horizontally, of course, and with room to work up a little velocity.) That leaves you with a net downward velocity of 90-95 feet per second. In short, Pancake City."

Pretty conclusive. HOWEVER, this example is taking on a massive terminal velocity of 100 feet per second. I'm not sure that the lift at work, were it to drop from the 3rd floor (whats that, say 60 ft ?) would reach that kind of speed in such a relatively short drop.

I still say I've got a chance...

 

[Spicy2]

I work in a building where the lift often gets stuck between floors and has been known to drop down a couple of floors without anyone being hurt - it has shaken people up though. I reckon from the third floor you would be ok, but doubt if you would survive a falling lift in the Empire State Building. I wouldn't suggest you test it out - they are very old lifts!

 

[DAVEYBOY]

You just wont take no for an answer will ya!!!!

 

[Icy Gull]

If you were plummeting at 150 miles an hour and you jumped at the last second you'd slow down to maybe 140 miles an hour, so you'd have about as much chance as if you hadn't jumped.

 

[Theatre of Trees]

If you did decide to jump when do you do it? How do you work out when the lift is going to hit the ground?

 

[Easy 10]

Well, this is only a theoretical question. If I was to try it out in real life though, I'd want a glass-bottomed lift so I could see the ground rushing up and time my jump accordingly.

Actually, even if I got the jump right, I'd probably end up impaled on a huge shard of glass anyway, so maybe thats not really workable either.

Perhaps David Blaine could try it.

 

[NMH]

what about if you packed a parachute?

Only joking, it's a bloody silly (original) question innit?

 

[seagull over spain]

Easy it may be best in future that on entering the lift you should jump up and down repeatedly and should it go into free fall and you survive then let us know

 

[Everest]

Work on the ground floor.

No sweaty nights wondering what would happen if the lift fell,
No workout on the stairs (stay your svelte self)

 

[Cian]

If your in a lift made by one of the well known frims (read Otis and Schindler) its impossible for them to fall anyway, as if the cable snaps, the "cage" expands and locks the lift into the shaft instantly.

 

[Tenngull]

OK, I just have to jump in here as I AM a physics prof. Sorry, but jumping won't help you one little bit. Since you were moving downward at the same speed as the elevator your little jump just gets superimposed on that downward plunge - its not independent of it. Even in the case that the levator (and you) had reached terminal velocity and you did manage to jump upward at the same (or a faster) speed as the elevator is moving downward, what goes up must come down. So you'd just hit the ground a fraction of a second later, at exactly the same speed as if you'd never jumped in the first place!

An analogy to think about is what would happen if you jumped upward on a moving train, or even better a plane moving at 500 mph. Since you are moving at the same speed as the plane you continue moving at that speed even during your jump - the back of the plane doesn't rush up and hit you in the back of the head!

 

[Tenngull]

Double post - Sorry!!!!

 

[perth seagull]

I agree, I've thought about this before because I also work in a building where I have to use a lift. But jumping would not help, even though it does sound good in theory. It would be similar to if there was a bar over head in the lift, and you jumped and hung on to the bar, with your feet being off the ground. You would still get crushed.

 

[dougdeep]

Good thread. Although you may be able to get your feet off the floor you wouldn't be moving upward, so all you would gain is a longer life, but only by a split second.

 

[cheeseroll]

ok,ok, since we've got prof's on this thread on a similar note, if i boarded a plane with a parrot on my shoulder and during the flight, the parrot started to fly, would the aircraft weight (payload) get lighter ?

 

[dougdeep]

I'll go for no, surely the downward pressure from it's wings would cancel out it's weight.

 

[Garry Nelson's Left Foot]

Bloody hell! When did science become so interesting?! When i went to school we learnt about how slag heaps form, the periodical table and what the different parts of flowers are called.
Not once did my teachers pose questions about lifts, jumping, aeroplanes and parrots...

Which subsequently means that because I know dick all about sience, I'm going to side with easy 10 and say 'yes, jumping in a falling lift will save you.' And all you people with your new age science mumbo jumbo about downforce and whatnot can't convince me otherwise.

 

[dougdeep]

Bloody hell! When did science become so interesting?! When i went to school we learnt about how slag heaps form, the periodical table and what the different parts of flowers are called.
Not once did my teachers pose questions about lifts, jumping, aeroplanes and parrots...

Which subsequently means that because I know dick all about sience, I'm going to side with easy 10 and say 'yes, jumping in a falling lift will save you.' And all you people with your new age science mumbo jumbo about downforce and whatnot can't convince me otherwise.

But surely you must agree that by jumping you are not going upwards, just down at a slower rate. But not slow enough to make any difference.
If you were on a bus, and threw a ball up it would come back to you, it wouldn't thump into the rear windscreen.

 

[Garry Nelson's Left Foot]

Yes, yes. But while i continue to misunderstand science I can believe that the rickety old lift that I use to get to the 11th floor every day isn't going to be the cause of my death...

So, I refuse to be blinded by your sophistic science and don't have to develop a phobia about the deathtrap i have to use everyday!

Don't listen to 'em easy. Jumping will save you!

 

[beorhthelm]

I was always amazed at the one our teacher used to do: A fly stop a train.

Basically, if a fly flies headfirst into a train going in the other direction, there must be a point in which that fly stops going one way and has yet to start being pushed the other way by the force of the train. For a very very small moment the fly is static and as it is contact with the train, so is the train. Therefore a fly can stop a train.

Id say your teacher was a bit crap then.

The fly will momentarily have a zero speed *relative* to the train. But the train will only be slowed by some unimaginably small fraction as the fly's momentum is imparted onto it.