physics question / skydiving weight

Norman said:
Does the parachute exert more or equal force compared to the weight of the object?
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More. The weight of the object plus the weight of the scale minus the drag on everything below the attachment point due to its motion through the air. The drag is assumed to be less that the weight of the scale.
 
A parachute does not make a sack of poop weightless in a gravitational field.
 
In an unaccelerated steady state descent, the actual object (bag full of stuff or a skydiver) would weigh the same as on the ground. However, the question is what would the scale read, correct? I would say it would equal the weight of the object plus the lifting force of the parachute. It would be like taking a fish scale and pulling on it in opposite directions with your hands.
 
SkyDog58 said:
In an unaccelerated steady state descent, the actual object (bag full of stuff or a skydiver) would weigh the same as on the ground. However, the question is what would the scale read, correct? I would say it would equal the weight of the object plus the lifting force of the parachute. It would be like taking a fish scale and pulling on it in opposite directions with your hands.
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This is exactly what I want to know.
What would a fish scale read in a steady descent with a parachute on top and a weight on bottom?
 
SixPapaCharlie said:
This is exactly what I want to know.
What would a fish scale read in a steady descent with a parachute on top and a weight on bottom?
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That is what I thought you meant and I believe my answer is basically correct though there could be additional considerations. However, by some of the responses it appears that others were answering the wrong question.
 
I think it would only be more than 100 if it was either accelerating or decelerating. I believe in steady descent it would stay 100
 
SixPapaCharlie said:
I think it would only be more than 100 if it was either accelerating or decelerating. I believe in steady descent it would stay 100
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Is a parachute EVER in a steady state condition ?:dunno:..

Or is it at the mercy of updrafts /downdrafts/ sideways wind shear, swaying back and forth, etc etc.. ..:dunno::dunno:
 
SkyDog58 said:
However, the question is what would the scale read, correct? I would say it would equal the weight of the object plus the lifting force of the parachute. It would be like taking a fish scale and pulling on it in opposite directions with your hands.
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Nope. Not even close.

How do you use a fish scale? You hang it from something and then hang your fish (or bag of blow) from that, right? Doesn't matter if the "something" is a hook on the ceiling, your hand, or a parachute as long as you are either stationary or at a constant velocity.
 
In stead of arguing about this and turning into another "treadmill thread", just go grab a scale, take it to an office building, and ride the elevator up and down. Report back!
 
Skip Miller said:
In stead of arguing about this and turning into another "treadmill thread", just go grab a scale, take it to an office building, and ride the elevator up and down. Report back!
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what if it is one of those weird doubledecker elevators?
 
Answer of consequence is always:
42
 
This is making my head hurt. But Ive decided the answer is E=MC2

QUOTE=overdrive148;1881009]:no:Some of the skydivers that operate here talk about that happening. No thank you! I don't actually know how bad the deceleration is but the sound from the ground is pretty loud and sudden![/QUOTE]

Lemme tell you about deceleration...

A 'typical' parachute opening takes about 8 or 9 seconds and the deceleration force is not that big a deal. About 7 years ago I had an opening that took maybe ONE second. The result was a compression fracture of my T7 vertebrae. It sucked in a large way. Back brace for 15 weeks.

As for a line-over, Ive had one. Yes, I cut it away. No nut-under to date.
 
I didn't have time to fact check this but a friend of a friend's brothers sisters cousin said a 100 lbs of blow weighs different in Compton then it would in Calabasas or Beverly Hills.
 
All of this depends on how much 6PC snorted on the way.

Sent from my Nexus 9 using Tapatalk
 
The answer as always is "it depends". Everyone who said the force on the parcel will be 100 lbs as long as the apparatus is falling at a steady rate. That said the reading on the scale won't necessarily match that force due to several other factors.

One is the already mentioned drag force (aka air resistance) on the parcel. With a small enough parachute and a large enough weight (i.e. a low density parcel) the drag force could be a significant fraction of the parcel's weight making the scale read near zero.

The other factors are likely to be much smaller and include the weight of the rope connecting the parcel to the scale, the drag force on that rope, the drag force on the portion of the scale that supports the parcel, and the reduction in gravity with altitude.
 
gismo said:
The answer as always is "it depends". Everyone who said the force on the parcel will be 100 lbs as long as the apparatus is falling at a steady rate. That said the reading on the scale won't necessarily match that force due to several other factors.

One is the already mentioned drag force (aka air resistance) on the parcel. With a small enough parachute and a large enough weight (i.e. a low density parcel) the drag force could be a significant fraction of the parcel's weight making the scale read near zero.

The other factors are likely to be much smaller and include the weight of the rope connecting the parcel to the scale, the drag force on that rope, the drag force on the portion of the scale that supports the parcel, and the reduction in gravity with altitude.
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My scale isnt that accurate. It cant tell the difference between 99.98 and 100
 
SixPapaCharlie said:
Ok so it would pull the same on the scales because the objects are still relative to one another and doesn't matter that they are falling
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As long as they are falling at a steady rate (not accelerating).
Just like a plane in a steady climb or descent - forces are balanced.
 
What if the bag was filled with cole slaw?
 
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