Equvialence of Gravity Weight and PSI

AI Thread Summary
The discussion centers on comparing the effects of gravity weight on Earth with the pressure experienced at extreme ocean depths, specifically the Mariana Trench. It is clarified that gravity is a downward force while pressure acts uniformly from all directions, making direct comparisons challenging. Participants note that while humans are mostly incompressible due to our water content, extreme pressure can still have significant physiological effects, such as collapsing lungs. The goal is to create a vivid analogy for a lecture on peer pressure, using exaggerated imagery to engage the audience. Ultimately, the conversation emphasizes the importance of using relatable metaphors to convey complex scientific concepts in a non-scientific context.
Tyler Munson
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I've been searching the web for an answer to my question without success, My question is...
Is it possible to equate the gravity weight we experience on Earth with the PSI you would experience in places as deep as the Mariana Trench at 10,994 meters which would approx. equal 16,000psi?
ex. Would it be like having a 5,000 tons of weight on top of you? Granted it 10 tons would have the same effect on the human body.
Any answers I've found seem to say that these forces are too different to compare.
Even the best educated guess would help since I have no point of refence. My goal with this answer is to enrich an illustration I'm using in a lecture on a non-science topic next weekend. Any assistance you can provide would be greatly appreciated.

Thanks,
Tyler
 
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The problem is that gravity is a purely downward force whereas pressure is pushing you from all directions.

Extremely high weight on top of you would flatten you. Extremely high PSI would squish you all over
 
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Tyler Munson said:
My goal with this answer is to enrich an illustration

i have no idea what idea it is you want to convey to your audience.Here's a picture of a flounder at the bottom of that trench. ..
see 3 minutes into www.youtube.com/watch?v=XMWj_47WXcs
He's swimming right along - light must be an unusual sensation to him , if he even has eyes...
upload_2019-2-23_20-47-23.png


since we're mostly water and water is incompressible the pressure wouldn't squish us like bugs (provided our lungs were filled with air at same pressure),
but our body chemistry isn't designed for such extreme pressure and below about 200 feet oxygen becomes toxic to us so divers have to breathe a special mix . .
So far as i know the record for human deep diving is around 1800 feet. see en.wikipedia.org/wiki/Deep_diving

some whales(another large brained mammal) dive to around 3000 meters...
see
https://news.nationalgeographic.com...whale-record-dive-depth-ocean-animal-science/Give us a sketch and maybe we can help you .
 

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Tyler Munson said:
Is it possible to equate the gravity weight we experience on Earth with the PSI you would experience in places as deep as the Mariana Trench at 10,994 meters which would approx. equal 16,000psi?
Not really. Weight is a body force which points uniformly downwards and pressure is a surface force which points inwards at each point. In a uniform gravity field there is a net force, but in a uniform pressure field there is no net force.
 
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Surely you've swum down to the bottom of a swimming pool and felt the pain in your ears as the pressure pushes your eardrums inward ?

16000 psi is 6153 X the pressure at the bottom of a six foot deep swimming pool.
That'd push your eardrums together at the center of your head:wink:...
...
Since you want something your audience can relate to, try this:
Humans aren't very compressible at all, as i said we're mostly water.
But were we mostly air like Otto the Autopilot from "Airplane",
we'd get compressed from six feet tall to four inches.
(basis - that's an eighteenfold reduction, and 18 is approximate cube root of 6153)

Whales have evolved folding ribs that let their chest collapse to follow their lungs inward as they dive, as described in that link.
 
jim hardy said:
Surely you've swum down to the bottom of a swimming pool and felt the pain in your ears as the pressure pushes your eardrums inward ?

16000 psi is 6153 X the pressure at the bottom of a six foot deep swimming pool.
That'd push your eardrums together at the center of your head:wink:...
On the other hand, the same pressure is squeezing your big toe. It feels nothing.
 
Anybody seen @Tyler Munson ? (@ still not working)

Halllooooo ---
 
jim hardy said:
Surely you've swum down to the bottom of a swimming pool and felt the pain in your ears as the pressure pushes your eardrums inward ?

16000 psi is 6153 X the pressure at the bottom of a six foot deep swimming pool.
That'd push your eardrums together at the center of your head:wink:...
...
Since you want something your audience can relate to, try this:

(basis - that's an eighteenfold reduction, and 18 is approximate cube root of 6153)

Whales have evolved folding ribs that let their chest collapse to follow their lungs inward as they dive, as described in that link.

This is closer to what I'm looking for, my goal is to describe experiencing extreme pressure and translating it to something kids would understand from items that they could typically experience. Such as stacking a ridicules amount of barbell on top of their shoulders to mimic the crushing weight or how many elephants it would take all stacked on top of you to approximate the same kind of crushing force that would take place 10,994 meters underwater in the Mariana Trench(not actually preforming such a demo though, I don't have that many elephants).?:)
This is all in an effort to relate to the how to cope with peer pressure they might deal with in school, that while the pressure maybe be unbearable, there are methods of not giving in.
jim hardy said:
Anybody seen @Tyler Munson ? (@ still not working)

I really do appreciate anyone/all of you, for taking the time to post on a question like this. I assure you I'm reading everything, I've had the flu, so it made it hard to do anything, including THINK.
 
Tyler Munson said:
Such as stacking a ridicules amount of barbell on top of their shoulders to mimic the crushing weight or how many elephants it would take all stacked on top of you to approximate the same kind of crushing force that would take place 10,994 meters underwater in the Mariana Trench
hmm. Try this at home first...

A hand or foot operated bicycle tire pump
with the hose removed and replaced by a pipe plug from the hardware store
should give a nice tactile demonstration of the relation between force and pressure.
upload_2019-2-26_0-28-6.png

picture credit to Wikipedia https://en.wikipedia.org/wiki/Bicycle_pump#/media/File:Bicycle_Pump_foot_operated.jpg

it takes a goodly force to make 100 psi with one of these, probably most of a kids' weight...
Let 'em try it.
Then point out it'd take 160 kids pushing that hard to make 16,000 psi and the needle would have to make a hundred turns.
and the pump would split open first.

They'll probably break your pump stomping on it to peg the gage,
and have a great time.

Then point out how powerful and subtle is peer pressure - they all tried to outdo one another ?

Good Luck !

old jim
 

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jim hardy said:
hmm. Try this at home first...

A hand or foot operated bicycle tire pump
with the hose removed and replaced by a pipe plug from the hardware store
should give a nice tactile demonstration of the relation between force and pressure.
View attachment 239368
picture credit to Wikipedia https://en.wikipedia.org/wiki/Bicycle_pump#/media/File:Bicycle_Pump_foot_operated.jpg

it takes a goodly force to make 100 psi with one of these, probably most of a kids' weight...
Let 'em try it.
Then point out it'd take 160 kids pushing that hard to make 16,000 psi and the needle would have to make a hundred turns.
and the pump would split open first.

They'll probably break your pump stomping on it to peg the gage,
and have a great time.

Then point out how powerful and subtle is peer pressure - they all tried to outdo one another ?

Good Luck !

old jim

this lecture is in front of 5,000, there isn't an ability of have an actual demonstration. So I'm trying to stimulate with the mind's eye with something way over the top as an introduction to capture attention in the minute of speaking on a 15 min lecture on peer pressure
 
  • #11
Tyler Munson said:
this lecture is in front of 5,000, there isn't an ability of have an actual demonstration. So I'm trying to stimulate with the mind's eye with something way over the top as an introduction to capture attention in the minute of speaking on a 15 min lecture on peer pressure
So the desire is for excitement rather than correctness as far as the physics goes. And this is to support an irrelevant analogy between physics pressure and peer pressure.

Form over substance. *sigh*.
 
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  • #12
Tyler Munson said:
this lecture is in front of 5,000, there isn't an ability of have an actual demonstration.
Why not? All you need for demonstrations is a little bit of space and if the venue is big, a video monitor so you can see better.

My very first physics class combined all sections in one big lecture hall - only around 100 people, but still - and it was entirely demonstrations of basic physics concepts.

Anyway, I see this is for a discussion of peer pressure. A visual aid for a non-science analogy doesn't have to be meaningful, much less accurate. Just decide what you want to say, and then think of a meaningless analogy that evokes a good visual. For example, people often describe a heart attack as feeling like an elephant sitting on your chest. Maybe you want to describe peer pressure the same way. A google image search yields lots of good visuals for that.
 
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  • #13
Yep
i'd get volunteers from the audience
call three boys to see how much pressure each can make
then call three girls
if there's any difference in competitiveness you have an interesting digression

i was watching a nature show not too long ago
an observant cameraman filming large primates caught a male showing off for female, when she left unimpressed he went back to his nap

call three boys and three girls up together and see if presence of the other sex makes a difference in behavior
https://www.scientificamerican.com/article/peer-pressure-has-a-positive-side/
The brains of teenagers, but not adults, showed greater activity in two regions associated with rewards (the ventral striatum and the orbitofrontal cortex) when they were being observed by same-age peers than when alone. In other words, rewards are more intense for teens when they are with peers, which motivates them to pursue higher-risk experiences

https://scholar.google.com/scholar?q=peer+pressure+psychology&hl=en&as_sdt=0&as_vis=1&oi=scholart

have fun, and make 'em think !
 
  • #14
jbriggs444 said:
So the desire is for excitement rather than correctness as far as the physics goes. And this is to support an irrelevant analogy between physics pressure and peer pressure.

Form over substance. *sigh*.

I'm sorry if you feel this is a waste of your time. I find that a wealth of information from a multitude of source has the ability to enrich the dialog, which makes the difference between a boring lecture and something they walk away remembering.

russ_watters said:
Why not? All you need for demonstrations is a little bit of space and if the venue is big, a video monitor so you can see better.

The forum in which this presentation is given doesn't allow for any videos or any volunteer participation .
I sincerely appreciate your assistance in trying to help me come to the conclusions I am looking for.
 
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  • #15
Let me ask it in a different way. How small would an average 200 lb. male body compress when under 10,000psi. The size of a bowling ball, or a grape, or what?
 
  • #16
Tyler Munson said:
Let me ask it in a different way. How small would an average 200 lb. male body compress when under 10,000psi. The size of a bowling ball, or a grape, or what?
Negligibly. The lungs would squeeze shut, of course. And you would have sinus problems. But the rest of the body is fluid-filled for the most part. Water is not very compressible.

Again, you seem to be looking more for "wowsa" rather than for science. One can do wowsa by taking off your clothes on stage. Talk about peer pressure. Actually, that might work...

Walk out there in a big fuzzy pink one piece bunny rabbit costume with floppy ears straight out of "A Christmas Story".
 
  • #17
Tyler Munson said:
How small would an average 200 lb. male body compress when under 10,000psi.

jbriggs444 said:
Negligibly. The lungs would squeeze shut, of course. And you would have sinus problems. But the rest of the body is fluid-filled for the most part. Water is not very compressible.

there's your lead in.
The metaphor is "You're stronger than you think. Peer pressure is all in your head."

we're brainwashed by Madison Avenue to feel dissatisfied and inadequate..
'Buy our orange soda and you too will be playing volleyball on the beach with twenty-somethings.'

Good luck - this could turn out a real thoughtful talk.
 
  • #18
photo-1-copy.jpg
 

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