iWitness - Air Pressure and Weight

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Quote from: sceptimatic on July 31, 2016, 02:35:40 AM

Quote from: crutonius on July 30, 2016, 12:31:07 PM

Quote from: sceptimatic on July 30, 2016, 12:05:47 PM

Quote from: crutonius on July 30, 2016, 10:24:18 AM

Quote from: sceptimatic on July 30, 2016, 09:10:26 AM

Quote from: crutonius on July 30, 2016, 08:56:51 AM

Quote from: sceptimatic on July 30, 2016, 08:35:44 AM

Quote from: sandmanMike on July 30, 2016, 08:30:42 AM

Quote from: sceptimatic on July 30, 2016, 08:01:58 AM

Not correct. It's still under equilibrium.

Could you explain?

If you allow atmospheric pressure to expand and exit out of a chamber, it will still leave an equal (all around inside) but less pressure inside of that chamber. So therefore anything inside it is simply still a dense object sitting inside under that pressure.

I would like some clarification on this as well. It seems like a pretty simple thing to test.

Get a vacuum chamber.

Put a kitchen scale in it.

Put a weight on the scale.

Evacuate the air and then observe.

Yep, as long as the test is done legitimately and not a con job like sokarul tried.

That's kind of the point. These discussions are only a start point.  It's all just a bunch of words until we put it to the test.

I've done this experiment so I can tell you what I've seen. You can my word for it or you can run it yourself. If your results differ from mine then we have to go over our procedures and see who botched what. But if you get the same results then you might have some problems with your theory that needs some work.

That's how falsification works and it takes a certain kind of masochism to perform without prejudice because it's essentially actively working to kill your own intellectual property.

Ok, well first of all, go and get a chamber for pressurising and evacuating. Then do the tests.

Go back and read what I've written more carefully. I have performed these tests.

Try and understand what I'm saying.

Adorable. You have your own pretend physics.

Alright. Have it your way. You just keep on believing that if it makes you feel better.

Just take things easy when you actually have to build things affected by gravity. You might get embarrassed.

I don't need to use gravity to build anything. Tell me why I need gravity?

Quote from: rabinoz on July 31, 2016, 06:48:10 AM

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

Quote from: Blue_Moon on July 30, 2016, 12:12:37 PM

Sceptimatic, iWitness, and Anarchist, I want you to listen to this. 

Imagine you're in the KC-135 "Vomit Comet," the plane used to train astronauts for microgravity.  The plane starts to accelerate downward at 9.8 m/s², and you start to become weightless, along with everything else inside the plane.  But the pressure in the plane hasn't changed at all, and you're not in contact with the outside air, so if weight is caused by pressure and density instead of gravity, how can that be?

Think of the dropped lift. If it dropped at the same speed as you fell and there were scales on the floor with you on them, then you would basically (as a man made weight measurement) weigh nothing.
Now imagine the lift ascends at speed and you are on those scales. You now appear to weigh a lot more due to the force upon you.

Basically in the plane or lift you are free falling (sort of) but due to your enclosed environment, you simply appear to float.
The plane pressurises a lot more on the dive, aiding in that apparent ease of free fall (float appearance).

Ascending in a lift at speed/acceleration is pushing you into atmosphere that is resisting that push. Think of a spring.
This creates more pressure upon you and it would be registered on a scale plate if you were stood on it.
It's made out to be G-force but the real name for it should be A-force.

No, the plane does not do anything with pressure to make you seem weightless.  It's all acceleration.  Anytime you're accelerated toward the earth at the same rate as G, in our case about 9.8 m/s², you feel weightless, regardless of whether the air around you is doing the same.  I'll give you another example: 


It's called a drop tower.  You may or may not have ridden on one before, but it lifts you and drops you.  I've been on a few of them in my lifetime.  I can tell you that you will feel weightless when you're being dropped, despite there being no enclosure around you to manipulate pressure. 

Quote from: sceptimatic on July 31, 2016, 09:24:29 AM

Quote from: rabinoz on July 31, 2016, 06:48:10 AM

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

Quote from: sceptimatic on July 31, 2016, 02:26:29 AM

Quote from: Blue_Moon on July 30, 2016, 12:12:37 PM

Sceptimatic, iWitness, and Anarchist, I want you to listen to this. 

Imagine you're in the KC-135 "Vomit Comet," the plane used to train astronauts for microgravity.  The plane starts to accelerate downward at 9.8 m/s², and you start to become weightless, along with everything else inside the plane.  But the pressure in the plane hasn't changed at all, and you're not in contact with the outside air, so if weight is caused by pressure and density instead of gravity, how can that be?

Think of the dropped lift. If it dropped at the same speed as you fell and there were scales on the floor with you on them, then you would basically (as a man made weight measurement) weigh nothing.
Now imagine the lift ascends at speed and you are on those scales. You now appear to weigh a lot more due to the force upon you.

Basically in the plane or lift you are free falling (sort of) but due to your enclosed environment, you simply appear to float.
The plane pressurises a lot more on the dive, aiding in that apparent ease of free fall (float appearance).

Ascending in a lift at speed/acceleration is pushing you into atmosphere that is resisting that push. Think of a spring.
This creates more pressure upon you and it would be registered on a scale plate if you were stood on it.
It's made out to be G-force but the real name for it should be A-force.

No, the plane does not do anything with pressure to make you seem weightless.  It's all acceleration.  Anytime you're accelerated toward the earth at the same rate as G, in our case about 9.8 m/s², you feel weightless, regardless of whether the air around you is doing the same.  I'll give you another example: 


It's called a drop tower.  You may or may not have ridden on one before, but it lifts you and drops you.  I've been on a few of them in my lifetime.  I can tell you that you will feel weightless when you're being dropped, despite there being no enclosure around you to manipulate pressure.

The same thing applies except as you feel weightless you still feel a breeze on your body from the external air.
It's no different to the lift, except one is enclosed and the other is not.

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Quote from: sceptimatic on July 31, 2016, 09:24:29 AM

Quote from: rabinoz on July 31, 2016, 06:48:10 AM

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

School physics.

http://practicalphysics.org/acceleration-due-gravity.html

Quote from: sceptimatic on July 31, 2016, 02:27:54 PM

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Quote from: sceptimatic on July 31, 2016, 09:24:29 AM

Quote from: rabinoz on July 31, 2016, 06:48:10 AM

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

School physics.

http://practicalphysics.org/acceleration-due-gravity.html

I actually thought - NAIVELY, that you were actually going to type something from your own.
Ahhh well, never mind.

Quote from: inquisitive on July 31, 2016, 02:41:08 PM

Quote from: sceptimatic on July 31, 2016, 02:27:54 PM

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Quote from: sceptimatic on July 31, 2016, 09:24:29 AM

Quote from: rabinoz on July 31, 2016, 06:48:10 AM

Quote from: sceptimatic on July 31, 2016, 06:22:26 AM

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Do you know that I find that a completely meaningless statement? Does anyone else?

How do YOU measure weight? How can we measure anything without using man-made instruments?
By the way, I suppose you know that you cannot measure weight with a balance type "weighing machine", that just compares masses.

Correct.

To know what you're balancing in terms of kg, etc, you must first set a weight scale measurement.
The point I'm making is, weight is the man made scale measurement by numbers, of the density of an object against atmospheric pressure.

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

School physics.

http://practicalphysics.org/acceleration-due-gravity.html

I actually thought - NAIVELY, that you were actually going to type something from your own.
Ahhh well, never mind.

Now you have no problem proving your belief, we await the results.

Quote from: sokarul on July 30, 2016, 01:34:03 PM

Quote from: iWitness on July 30, 2016, 12:58:48 PM

Congratulations! The experiment proves a Bowling Ball is more dense (heavier) than little to no air (i doubt a true vacuum is even possible).

Density does not mean weight.

Not in your indoctrinated law but in reality it is the direct cause of the man made  scale measurement that determines the density against atmospheric resistance to it.

Density is mass over volume. If you have a problem with this write to NIST.

Quote from: sokarul on July 30, 2016, 12:38:10 PM

But high density materials still weigh different. An empty gas cylinder will weigh less than a full one, but no air gets in when it's empty or full. You cannot explain this.

You've just answered your own question.

I did, you cannot explain this. That is why you didn't.

Stop claiming the same thing over and over. I have already shown you mean times to be wrong.

You do seem mean but you've shown me nothing except bullshit. You did not follow my instructions and you know it.
[/quote]
lol
No change in weight was seen. No change in weight on top of mountains is seen.
lol
Keep crying about denpressure though.

lol

Millionaire North Korean can't even spend $300 to prove denpressure.

lol

Keep living in your pretend world though, I know your real world is shit. So shit you had to invent a pretend world to live in.

lol

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

Air (or water) pressure cannot possibly cause what we call "weight" simply because air is a fluid.

Yes, it's a much less dense fluid. Water is more dense. Weight is simply a man made measurement by a man made scale using a solid base as leverage to repel/push against atmosphere and measuring the push of anything placed upon that scale plate against that atmosphere to give a reading of what we know as, WEIGHT.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

Pressure in a fluid always causes a force at right-angles to the surfaces of any objects in it.

Either by push into atmosphere or by grip of atmosphere upon the surface and sides, against the leverage of the solid ground.

The atmosphere (or any static fluid) cannot pull anything. Static fluids can only push.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

So if we have a horizontal flat sheet the force pressing down on the top surface is balanced by an equal force pressing up on the bottom.

No it's not. The solid floor is a resistant force that stops the push of the plate against the atmosphere above from pushing it further down. A resistance of the actual area and width of the sheet, plus the density of it.

A solid thin sheet has the same force of the atmosphere pressing on the top and the bottom! There are no two ways about it - that is a fact. Get yourself an absolute reading pressure gauge and it will read exactly the same whichever way you point the inlet.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

It does not matter how high or low the pressure is the same thing applies, as long as the pressure on the top is the same as the pressure on the bottom. So the pressure does not cause any nett downward force, so does not contribute to weight.

It does matter. the higher the pressure means the higher the squeeze of any object or fluid/gas, meaning the potential for that object/fluid/gas gets squeezed upwards, or floats to our perception.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

Now we know from measurements that the air pressure gets lower as we increase in altitude.

Yes, I agree with that.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

Intuitively it would seem that this cannot be a very great amount, but it is more than we realise. A helium balloon floats simply because the air pressure pressing up from underneath is slightly greater than the air pressure pushing it down.

Correct. Just remember though that the atmosphere is SQUEEZING the less dense object (helium balloon for instance) UP and will continue to do so until the atmosphere reaches equilibrium, in which case we would see the balloon simply appear to hover or float, but usually would pop due to the balloon losing it's elasticity.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

The amount of this lift can easily be calculated. A cubic metre of air (at STP^[1]) weighs 1.225 kg, so the air pressure decreases by 1.225 kg per square metre for each metre increase in altitude. This sounds a lot until it is realised that the normal air pressure is 10,340 kg/m².

So back to our funny cube shaped helium balloon, the total force caused the pressure on the bottom is 1.225 kg more than the force on the top, so there is a nett uplift of 1.225 kg.

Now of course we have to subtract from this the weight of the balloon. If we can neglect the weight of the balloon skin, the weight of the helium would be its density (0.164 kg/m³) times its volume (1 m³), or 0.164 kg.

So a 1 cubic metre helium balloon has a buoyancy of just over 1 kg, less the weight of the balloon structure. 

There's really no need to go into this. This just adds nothing to the understanding.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

In the end the shape of the balloon makes no difference and the "lift" is simply the

(density of the air displaced) x (the volume of the object)

In other words Archimedes Principle.

Quote from: rabinoz on July 31, 2016, 01:09:21 AM

So, certainly density comes into working out buoyancy,

but pressure cannot cause weight, because the forces caused by pressure act equally in all directions.

[1] STP is short for Standard Pressure and Temperature, ie sea level,  etc.

Shape simply makes for a better uplift.

You claim "Shape simply makes for a better uplift." That is completely wrong, the shape of an object has no effect at all on its weight.

You talk "gobbledegook" (now there's a nice old fashioned word) and you ideas are simply not borne out in practice.
As soon as we suggest something that goes against you ideas, you claim that it is because of so"man-made" instrument.
But you seem unable to suggest some way to make a measurement under those conditions.

Take a simple case. And object does not weigh more when it is pushed deeper into water, in fact it might weigh a little less.
How do you suggest we verify this by measurement. I know how I would do it.

Wait a minute. Does this mean that in areas of low atmospheric pressure (i.e. during a cyclone) we would weigh less?

I thought you left. Care to answer some of the questions back in the other thread?

Eg. If you are floating in space, and a ball is in front of you, and you slap the ball as hard as you can, what would happen?

It would hurt like a mother.

If you are floating in space, and a ball is in front of you, and you slap the ball as hard as you can, what would happen?

He would probably punch you in the face.

Quote from: origamiscienceguy on July 29, 2016, 12:38:51 PM

If you are floating in space, and a ball is in front of you, and you slap the ball as hard as you can, what would happen?

He would probably punch you in the face.

I have a solution for the spherical chickens in a vacuum algorithm?    Seems like a spherical chicken would approximate a one to one mapping to a ball?

For those who haven't studied physics,  and don't get the joke,  don't ask me google it.
 

No, Air Pressure is the force that pushes denser objects DOWN aka "Gravity".

Weight is caused by Density. What makes a Bowling Ball "heavier" than a Watermelon? It's the Density.

Air pressure provides force proportional to area, not proportional to density.  You can hold any object of the same size out of the car window and it will experience the same force due to the wind, whether it's paper or leather or metal - the force will not be proportional to the density of the object itself.  That's why a 1-inch-thick sheet of cardboard will be picked up by the wind while a one-inch-thick sheet of steel will not.

Gravity acts differently than air pressure - it acts proportional to the mass of the object, while air pressure doesn't.  So you know the force causing things to fall towards the earth is not primarily due to air pressure.

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

Not at all.  When Galileo was studying gravity, he would roll balls of different weights down a ramp in order to slow the rate at which things fell.

Quote from: sceptimatic on July 31, 2016, 02:27:54 PM

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

Not at all.  When Galileo was studying gravity, he would roll balls of different weights down a ramp in order to slow the rate at which things fell.

I thought people like you went with the same sized object but different density fall at the same time. Are you now changing from this?

Air pressure provides force proportional to area, not proportional to density.

No it doesn't. It's density of any object/matter.

You can hold any object of the same size out of the car window and it will experience the same force due to the wind, whether it's paper or leather or metal - the force will not be proportional to the density of the object itself.

No you can't. It will not be the same at all.
That's like saying helicopter blades can be made of steel or paper or leather, etc.

  That's why a 1-inch-thick sheet of cardboard will be picked up by the wind while a one-inch-thick sheet of steel will not.

Yes because the steel sheet is much more dense and can repel more atmospheric pressure, meaning it is pushed against the deck with more force as it resists that push.Cardboard is already saturated with atmospheric pressure, leaving little to repel .

Gravity acts differently than air pressure - it acts proportional to the mass of the object, while air pressure doesn't.

Gravity is just a made up name with different sayings that really only mean atmospheric pressure upon dense objects, or denpressure.

  So you know the force causing things to fall towards the earth is not primarily due to air pressure.

It is everything to do with atmospheric pressure. Everything on Earth works because of it. No gravity needed and no magic to make the gravity con work. Just good old atmospheric pressure.

If air is stacked and pushing objects down (even though air pressure is greater beneath an object), what is pushing the topmost layer of air molecules down on the molecules below?

If air is stacked and pushing objects down (even though air pressure is greater beneath an object),

It's a push against resistance both ways with object and atmosphere. Atmosphere can only push back on something pushing into it to cause it to push back, or resist that push into it; whichever way you wan t to look at it.

what is pushing the topmost layer of air molecules down on the molecules below?

Basically, nothing.
Imagine you are the last molecule and you're laid on your bed face down. Your body density is being resisted by the mattress and then the bed frame and then the floor and then the joists. Your back and everything facing up has no force upon it so it has nothing to push against. It becomes dormant. It freezes against a true vacuum (possibly) but your front is still resting on the mattress molecule which in turn is resting on the bed molecule which is resting on the floor molecule, etc, etc, etc.


Your back

I'm sorry, I was typing a long post here and then just wiped everything.
All this thread is a chunk of nonsense. It's so stupid I wouldn't even comment.
Atmospheric pressure causes weight? Are you mad? So on planets where there is almost no atmospheric pressure, there is no force pulling things toward they center? Why asteroids fall on surface of Mercury, Mars and Moon?

No you can't. It will not be the same at all.

Sure it will.  Shall we perform an experiment and find out?

That's like saying helicopter blades can be made of steel or paper or leather, etc.

Helicopter blades need to be made of something solid enough to stay rigid against the air that they are pushing.  The force of air would be the same for the same size, but paper or leather blades would not be strong enough for the force.
This is why wind power blades, for example, are now being made out of lightweight carbon composite instead of steel.  The same size blade receives the same force from the wind regardless of what it's made of, but the carbon composite is strong enough to stay rigid against the air while being light enough to lose significantly less energy from friction and strain on the mechanisms.
If what you are saying is true, then it would make sense to make wind power blades out of the densest material possible to harness more wind energy - but that is the opposite of what they are doing.

Quote from: AdamSK on August 01, 2016, 07:14:30 AM

  That's why a 1-inch-thick sheet of cardboard will be picked up by the wind while a one-inch-thick sheet of steel will not.

Yes because the steel sheet is much more dense and can repel more atmospheric pressure, meaning it is pushed against the deck with more force as it resists that push.Cardboard is already saturated with atmospheric pressure, leaving little to repel.

I thought you said the air pushes much harder on the steel than it does on the cardboard.  Why doesn't the steel move as easily as the cardboard?

Let's say I set up two identical lightweight carts on wheels, and attach each one to a stationary pole with an identical spring.  I give both carts sails of the same thickness and area, but one of the carts has a steel sail and the other a cardboard sail.  I then turn on a large fan to blow air on each of them, and measure how much the springs contract.

What does your model predict that I would measure, and why?  Will the cart with the steel sail cause its spring to contract by roughly the same amount (indicating it is experiencing the same force from the wind), or significantly more (indicating the wind is pressing harder against it), or less (indicating the wind is pressing not as hard against it)?

Quote from: 29silhouette on August 01, 2016, 08:55:30 AM

If air is stacked and pushing objects down (even though air pressure is greater beneath an object),

It's a push against resistance both ways with object and atmosphere. Atmosphere can only push back on something pushing into it to cause it to push back, or resist that push into it; whichever way you wan t to look at it.

Still seems odd that it only works in a downward direction, and with pressure underneath still being more than on top.

Quote from: 29silhouette on August 01, 2016, 08:55:30 AM

what is pushing the topmost layer of air molecules down on the molecules below?

Basically, nothing.
Imagine you are the last molecule and you're laid on your bed face down. Your body density is being resisted by the mattress and then the bed frame and then the floor and then the joists. Your back and everything facing up has no force upon it so it has nothing to push against. It becomes dormant. It freezes against a true vacuum (possibly) but your front is still resting on the mattress molecule which in turn is resting on the bed molecule which is resting on the floor molecule, etc, etc, etc.


Your back

So if nothing is pushing that layer down, then nothing is pushing the next layer down, all the way to the ground.  Why is there any downward push on an object? 

I'm sorry, I was typing a long post here and then just wiped everything.
All this thread is a chunk of nonsense. It's so stupid I wouldn't even comment.
Atmospheric pressure causes weight? Are you mad? So on planets where there is almost no atmospheric pressure, there is no force pulling things toward they center? Why asteroids fall on surface of Mercury, Mars and Moon?

There's no such thing as planets and asteroids and what not. All that stuff is gunk. It's nonsense, just like a silly spinning Earth is absolute nonsense.

Atmospheric pressure doesn't cause weight. Man invents weight by inventing a measuring device, called a scale to show a reading of any object placed upon that scale against atmospheric pressure, where the object resists the pressure of atmosphere by using the scale plate as a resistant area in order to stop being pushed down.
The scale plate is designed to give way to that pressure which shows as a reading of what we call, weight.

Students and people of this Earth are duped into believing that a fictional force of gravity that isn't a force but is a force when needed but not a force when magical things need explaining...and so on and so on and so on.

Start thinking for yourself. Seriously.

Quote from: neutrino on August 01, 2016, 09:34:57 AM

I'm sorry, I was typing a long post here and then just wiped everything.
All this thread is a chunk of nonsense. It's so stupid I wouldn't even comment.
Atmospheric pressure causes weight? Are you mad? So on planets where there is almost no atmospheric pressure, there is no force pulling things toward they center? Why asteroids fall on surface of Mercury, Mars and Moon?

There's no such thing as planets and asteroids and what not. All that stuff is gunk. It's nonsense, just like a silly spinning Earth is absolute nonsense.

Atmospheric pressure doesn't cause weight. Man invents weight by inventing a measuring device, called a scale to show a reading of any object placed upon that scale against atmospheric pressure, where the object resists the pressure of atmosphere by using the scale plate as a resistant area in order to stop being pushed down.
The scale plate is designed to give way to that pressure which shows as a reading of what we call, weight.

Students and people of this Earth are duped into believing that a fictional force of gravity that isn't a force but is a force when needed but not a force when magical things need explaining...and so on and so on and so on.

Start thinking for yourself. Seriously.

How do I calculate the acceleration of falling pieces of different metals of the same size?

Quote from: markjo on August 01, 2016, 07:42:37 AM

Quote from: sceptimatic on July 31, 2016, 02:27:54 PM

Quote from: inquisitive on July 31, 2016, 10:47:20 AM

Still waiting for your proof that same size objects of lead and aluminium fall at different speeds.

I don't have a skyscraper to prove this, so it's going to be physically hard to prove and you know this.

Not at all.  When Galileo was studying gravity, he would roll balls of different weights down a ramp in order to slow the rate at which things fell.

I thought people like you went with the same sized object but different density fall at the same time. Are you now changing from this?

Not really.  If air resistance is ignored, then objects with different densities will fall at the same rate.  However, air resistance can and will affect less dense objects far more than more dense objects.  For very low density objects, buoyancy can become a significant factor as well.

Atmospheric pressure doesn't cause weight. Man invents weight by inventing a measuring device, called a scale to show a reading of any object placed upon that scale against atmospheric pressure, where the object resists the pressure of atmosphere by using the scale plate as a resistant area in order to stop being pushed down.

So you agree that a force exerted on a spring will compress the spring in proportion to the amount of force.  Yes?

What will happen if I put two same-size blocks on wheels, one made of solid wood and one made of cardboard, I put springs horizontally between them and a wall, and I blow on both with a fan?  Will they compress the spring the same amount?
Your model would require, I think, that the block of solid wood would compress the spring more than the cardboard block.  That is, after all, how it is that the solid wood block "weighs" more when you set it on a vertical spring according to your model.  In contrast, in my model the springs would be compressed the same amount.

Do you agree with what I claim your model would predict?  Because, if so, we have a physical test of both models to determine which one is correct.  Right?

Scepti

If you consider yourself a FE scientist, or what ever you prefer to call it, you really need to take a long hard look at the questions people are posting here.

Lets just say you are on the right track.  If you ignore the tough questions and just wave them away your hypothesis will remain just that.

Your denpressure hypothesis fails to answer many questions adequately and I assume you do not consider yourself all knowing and infallible.  Good scientist not only look at what proves them right, but also what proves them wrong. 

Questions denpressure fails to answer:

What keeps the atmosphere in place?  Nature likes balance and pressure will equalize unless some thing prevents it from happening.  Why does the atmosphere not move towards the vacuum of space?

Why does the atmosphere become denser at lower altitudes?  Simple experiments can be conducted to show that a liquid of the same density will not do this unless something is acting on it.

Why do things fall at the same rate regardless of the surface area or density? Want to see this for yourself make a vacuum chamber and drop different things in it.

Why does it require less energy to move horizontally then it does to move upward? If what is holding me on the ground is air pressure and it is acting equally in all directions.

I will leave it a that.