Bungee jump goes wrong but a question

she is 3 seconds away from the water it looks like so still quite high above the water, haven't you seen the pictures of her?
 
Energize said:
Weight is important only when terminal velocity is reached, which would not happen within 3 seconds for a human. Drop a human and a mouse off a plane though and the human will hit the ground much earlier because it's heavier, regardless of drag and surface area.

Though drag coefficients, fluid density and surface area do need to be taken into account to get an very accurate estimation of how far she fell, it's impossible to obtain from the video and is not a big factor here.

Using the equation S=1/2at^2 then assuming the bungee broke at it's greatest point of stress, ie when her initial velocity was about 0, she would have fallen 44m or 144ft. Not taking into account aforementioned drag or surface area.
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Weight is irrelevant.

Why have you wrote a load of rubbish after a fundamental error. If weight was the only factor how do skydivers control there falling speed?
 
Lucero said:
The snapped part of the cord (as in, the actual part where it snapped), hit the water before she did. She must have been on her way back up and probably not that far above the water at all
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This - it's not a simple case of straight down, some of that three second delay she could actually have been coming UP before going down.
 
It depends how much the cord slowed her down before it snapped suerly and not simply the height so it is impossible to work out, however looking at her bruises it wasn't good.
 
Vanilla said:
This - it's not a simple case of straight down, some of that three second delay she could actually have been coming UP before going down.
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If you look at the pictures I captured above, the cord broke as soon as she hit the bottom of her fall.
It might have slowed her down a tad but I don't think she ever came back up.
 
Simon said:
Weight is irrelevant.

Why have you wrote a load of rubbish after a fundamental error. If weight was the only factor how do skydivers control there falling speed?
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Mass is relevant in the example he cited, however saying "regardless of drag and surface area" was a bit misleading.

If you have two objects of which one is lighter, the force due to acceleration (F=ma) will be lower, meaning as it picks up speed and the drag due to air resistance increases, the upwards drag force will equal the downwards acceleration force faster than with a heavier object.

It is of course heavily dependent on drag, as if you have a light object with a very low drag coefficient the force will take much longer to equalize compared to that of a high drag coefficient of the same weight.
 
Simon said:
Weight is irrelevant.

Why have you wrote a load of rubbish after a fundamental error. If weight was the only factor how do skydivers control there falling speed?
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Google terminal velocity, it's highly dependent on weight. ;)

I never said weight was the only factor. I actually said
drag coefficients, fluid density and surface area do need to be taken into account
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In my example the weight differential is so great that regardless of the drag that may be produced the human is going to fall first.
 
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Bungy ropes are quite often frayed anyway, as they're overbuilt to try and prevent incidents like this. But this is a prime example of why I'd only go bungy jumping at an AJ Hackett location or similar. They use the ropes for X amount of jumps and then ditch them regardless.
 
Energize said:
In my example the weight differential is so great that regardless of the drag that may be produced the human is going to fall first.
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I think "regardless of drag etc" was the wrong choice of words, it makes it sound like they don't have an influence at all.
 
gillywibble said:
*Daft Question Alert*

Would the velocity of the rope have an impact upon the velocity of the person?
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Could do, but I don't think it would be a rope if it did. I think the rope is in free fall as soon as you jump and therefore has no tension. But if the rope was an odd shape and had a large drag coefficient, then it would pretty much be like a parachute.
 
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