Simple Balloon "Rocket"...

fyi  steel is 7850 kg/m3, al is 2720.

fyi  steel is 7850 kg/m3, al is 2720.

So it's 2.9 times heavier rather than ~3 times heavier, depending on alloy. I think I can live with that.

LOL... I can see why any thread that sceptimatic gets involved with usually stretches into 80 or 90 pages.

Today, alone, in this thread our resident mental midget has posted thirty-three comments!  And each and every one of them has been a farrago of absurd, nonsensical claims unsupported by even the tiniest iota of empirical evidence.

He's still failed to define his theory of "denpressure" which he alleges is a "combination" of density and pressure, which are of course two totally different entities and can't be "combined".  He can't even tell us its alleged units of measure, or whether it's a scalar or a vector quantity.  It was total bullshit 6 months ago, and it's still total bullshit today.

He obviously still can't understand the differences between weight and mass, or between force and pressure.  He also confuses a material's density with its porosity, and seems to have never heard of Archimedes.  There's just so much basic high-school science that this poor sap doesn't understand, you'll get more intelligent responses from a trained cockatoo LOL.

It's really pointless even encouraging him further with his dimwitted comments by repeatedly responding to his each and every comment here.  I guess at the very least, his presence here has similar entertainment value to Bozo the Clown at a circus.

—And they do say laughter is the best medicine.   

Quote from: inquisitive on November 23, 2014, 11:58:59 AM

Quote from: sceptimatic on November 23, 2014, 11:44:44 AM

Quote from: sokarul on November 23, 2014, 11:40:17 AM

Instead of explaining, prove it.

Explanations should be easy to grasp. When you prove gravity, I'll prove denpressure. You first.

So you cannot.

Bin for you as well.

You say this like it is a punishment 

Quote from: sceptimatic on November 23, 2014, 12:02:07 PM

Quote from: inquisitive on November 23, 2014, 11:58:59 AM

Quote from: sceptimatic on November 23, 2014, 11:44:44 AM

Quote from: sokarul on November 23, 2014, 11:40:17 AM

Instead of explaining, prove it.

Explanations should be easy to grasp. When you prove gravity, I'll prove denpressure. You first.

So you cannot.

Bin for you as well.

You say this like it is a punishment 

A punishment for what? the reason why I bin people is so they know not to waste their time answering me and I can deal with those that can grasp stuff without going into spasms.
When I try to explain stuff in basic, some of these people cannot grasp it because they have been mind warped to accept numbers and silly equations for what they have been told to believe and think that grasping the alterneative requires the same.

Here's a simple example.
Gravity cannot be proven at all as a force of any description, except for science to mention mass pulling mass or coming up with stupid warped space time which means absolutely nothing, except that it sounds magically scientific for those that love to hang onto this crap.

The real shocker is, they can calculate it all. Something they do not know. If you don't find that odd then I'm wasting my time trying to explain the reality.
So as far as punishment goes, it's a bit silly saying that when the reality is, these people would prefer me not to be here in the first place because I'm one mind against what they are trained to believe, same as you are and why you are following them into the bin for a week, as well.
Punishment? nah, it's basically because it's easier for me to put my thoughts out and deal with people who have a brain that can think and ignore those that simply try their best to disrupt that or basically go clueless in understanding logic and common sense.

It's easier to see "you are ignoring this user" than to have to see the words they put, knowing exactly what it's going to be.

No need to reply to this, crabby.

Denpressure sucks.

Denpressure sucks.

It's all push against push. No sucking. 

Quote from: JimmyTheCrab on November 24, 2014, 02:00:54 AM

Quote from: sceptimatic on November 23, 2014, 12:02:07 PM

Quote from: inquisitive on November 23, 2014, 11:58:59 AM

Quote from: sceptimatic on November 23, 2014, 11:44:44 AM

Quote from: sokarul on November 23, 2014, 11:40:17 AM

Instead of explaining, prove it.

Explanations should be easy to grasp. When you prove gravity, I'll prove denpressure. You first.

So you cannot.

Bin for you as well.

You say this like it is a punishment 

A punishment for what? the reason why I bin people is so they know not to waste their time answering me and I can deal with those that can grasp stuff without going into spasms.
When I try to explain stuff in basic, some of these people cannot grasp it because they have been mind warped to accept numbers and silly equations for what they have been told to believe and think that grasping the alterneative requires the same.

Here's a simple example.
Gravity cannot be proven at all as a force of any description, except for science to mention mass pulling mass or coming up with stupid warped space time which means absolutely nothing, except that it sounds magically scientific for those that love to hang onto this crap.

The real shocker is, they can calculate it all. Something they do not know. If you don't find that odd then I'm wasting my time trying to explain the reality.
So as far as punishment goes, it's a bit silly saying that when the reality is, these people would prefer me not to be here in the first place because I'm one mind against what they are trained to believe, same as you are and why you are following them into the bin for a week, as well.
Punishment? nah, it's basically because it's easier for me to put my thoughts out and deal with people who have a brain that can think and ignore those that simply try their best to disrupt that or basically go clueless in understanding logic and common sense.

It's easier to see "you are ignoring this user" than to have to see the words they put, knowing exactly what it's going to be.

No need to reply to this, crabby.

tl;dr

sceptimatic obviously neglected to take his medications this morning.

Again.   

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">


Edit: for those who are genuinely interested; try and look past the expected onslaught of attempted ridicule. It's normal, so don't let it sway your thoughts. Use your own brain. that's all I ask.

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">

What's wrong with the explanation given at the end of the video?

Also, how does your denpressure differ from the already well understood principle of buoyancy?

Oh scepti is rebuttling my argument and also ignoring me. How quaint.

Nobody is denying that pressure exists. What the video was meant to illustrate is that as far as atmospheric pressure is concerned, it pushes up.

This just shows how ridiculous it is to argue with scepti. He can't even comprehend what he is reading.

Quote from: sceptimatic on November 24, 2014, 09:12:51 AM

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">

What's wrong with the explanation given at the end of the video?

Also, how does your denpressure differ from the already well understood principle of buoyancy?

The explanation is fine, except they missed out an important part of the explanation. The reason for this is because it destroys gravity if they add it in. Something I've been trying to tell you people for long enough. Can you see what they've missed out?

Quote from: markjo on November 24, 2014, 09:35:25 AM

Quote from: sceptimatic on November 24, 2014, 09:12:51 AM

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">

What's wrong with the explanation given at the end of the video?

Also, how does your denpressure differ from the already well understood principle of buoyancy?

The explanation is fine, except they missed out an important part of the explanation. The reason for this is because it destroys gravity if they add it in. Something I've been trying to tell you people for long enough. Can you see what they've missed out?

No, they basically said that the vacuum pulling the water up was stronger than the gravity pulling the water down.

Quote from: sceptimatic on November 24, 2014, 09:43:58 AM

Quote from: markjo on November 24, 2014, 09:35:25 AM

Quote from: sceptimatic on November 24, 2014, 09:12:51 AM

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">

What's wrong with the explanation given at the end of the video?

Also, how does your denpressure differ from the already well understood principle of buoyancy?

The explanation is fine, except they missed out an important part of the explanation. The reason for this is because it destroys gravity if they add it in. Something I've been trying to tell you people for long enough. Can you see what they've missed out?

No, they basically said that the vacuum pulling the water up was stronger than the gravity pulling the water down.

That wasn't the explanation. It was that the air pressure underneath the card is pushing up.

Quote from: sceptimatic on November 24, 2014, 09:43:58 AM

Quote from: markjo on November 24, 2014, 09:35:25 AM

Quote from: sceptimatic on November 24, 2014, 09:12:51 AM

A little earlier in this thread, Rottingroom put up this video to supposedly kill off denpressure and prove gravity. It actually destroyed gravity and proved that my theory of denpressure is correct. Can anyone see why?

Have a good look at it from both sides of the coin and tell me what you think is happening.
If no one sees why denpressure is the reason for this, I will explain it very simply. All you have to do is to think about what I said in this thread and use your brain.

" class="bbc_link" target="_blank" rel="noopener noreferrer">

What's wrong with the explanation given at the end of the video?

Also, how does your denpressure differ from the already well understood principle of buoyancy?

The explanation is fine, except they missed out an important part of the explanation. The reason for this is because it destroys gravity if they add it in. Something I've been trying to tell you people for long enough. Can you see what they've missed out?

No, they basically said that the vacuum pulling the water up was stronger than the gravity pulling the water down.

The vacuum pulling the water up? are you literally being serious here?
How about explaining this a little.

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Incorrect. My goal in this thread has been to squeeze enough detail about your denpressure so that it could be meaningfully tested. You don't want that to happen, fine. Then you shouldn't be saying anything about people 'believing in unproven theories', you might get the point, or not.

At least do the courtesy of telling how the scale in vacuum chamber test was wrong in your opinion. It was fake because it wasn't HD or because it destroyed your idea?

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

I bet that if we turned the cup over, the card would no longer keep the water in. We could jolt the glass upward and the water would push the card out of the way.

Seriously, you don't understand what the point of the vid was.

Quote from: sceptimatic on November 24, 2014, 10:15:24 AM

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Incorrect. My goal in this thread has been to squeeze enough detail about your denpressure so that it could be meaningfully tested. You don't want that to happen, fine. Then you shouldn't be saying anything about people 'believing in unproven theories', you might get the point, or not.

At least do the courtesy of telling how the scale in vacuum chamber test was wrong in your opinion. It was fake because it wasn't HD or because it destroyed your idea?

Do you know what's happening in the video. If so, explain it. You can yap on all you want about testing this and that. The proof is in your face. It doesn't require figures and crap equations to see that gravity is an absolute pile of crap and denpressure is reality.

Quote from: neimoka on November 24, 2014, 10:19:58 AM

Quote from: sceptimatic on November 24, 2014, 10:15:24 AM

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Incorrect. My goal in this thread has been to squeeze enough detail about your denpressure so that it could be meaningfully tested. You don't want that to happen, fine. Then you shouldn't be saying anything about people 'believing in unproven theories', you might get the point, or not.

At least do the courtesy of telling how the scale in vacuum chamber test was wrong in your opinion. It was fake because it wasn't HD or because it destroyed your idea?

Do you know what's happening in the video. If so, explain it. You can yap on all you want about testing this and that. The proof is in your face. It doesn't require figures and crap equations to see that gravity is an absolute pile of crap and denpressure is reality.

What's happening is that the card keeps the water from spreading apart and falling out, because with the card the water acts more like a solid object. It's like a piston in a cylinder. Vacuum forms on the closed top of the inverted glass preventing the 'piston' from leaving the 'cylinder'. That is my understanding of it, knowing that the water won't stay in there if you take the card off. You might deny that ofc and argue that denpressure keeps the water in there with or without the card, that's your prerogative.

Proof is in that denpressure has failed and will fail any practical test. You're so sure of yourself why don't you enlighten us on how much more water a steel block displaces than an aluminium block of same size. It's because you know full well that your idea is a failure, that's my guess. How did that story of yours go again, the one about people believing in unproven ideas?

If no one sees why denpressure is the reason for this, I will explain it very simply.

I can see the pressure reason for this, just not the den bit.

Take us through it big boy.

]The vacuum pulling the water up? are you literally being serious here?
How about explaining this a little.

Here is excerpt from a site with a more detailed explanation:

Isn’t the weight of the water enough to overcome the atmospheric pressure pushing against the card? That’s what most people would think, but if you look at the top of the glass of water (formerly the bottom), you’ll notice a small pocket of air. Actually there isn’t much of an opportunity for air to get into that space, so what we’ve created is a small pocket of low pressure (a place where there really isn’t that many air molecules). There are more air molecules pushing up against the bottom of the note card, creating a higher pressure area compared with the lower pressure area inside the air pocket in the glass. The force from the atmospheric pressure holds the card up and the low pressure zone in the glass prevents the water’s weight from pushing the card down.

So yes, a small volume of low pressure, also known as a (partial) vacuum.

Quote from: sceptimatic on November 24, 2014, 10:24:59 AM

Quote from: neimoka on November 24, 2014, 10:19:58 AM

Quote from: sceptimatic on November 24, 2014, 10:15:24 AM

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Incorrect. My goal in this thread has been to squeeze enough detail about your denpressure so that it could be meaningfully tested. You don't want that to happen, fine. Then you shouldn't be saying anything about people 'believing in unproven theories', you might get the point, or not.

At least do the courtesy of telling how the scale in vacuum chamber test was wrong in your opinion. It was fake because it wasn't HD or because it destroyed your idea?

Do you know what's happening in the video. If so, explain it. You can yap on all you want about testing this and that. The proof is in your face. It doesn't require figures and crap equations to see that gravity is an absolute pile of crap and denpressure is reality.

What's happening is that the card keeps the water from spreading apart and falling out, because with the card the water acts more like a solid object. It's like a piston in a cylinder. Vacuum forms on the closed top of the inverted glass preventing the 'piston' from leaving the 'cylinder'. That is my understanding of it, knowing that the water won't stay in there if you take the card off. You might deny that ofc and argue that denpressure keeps the water in there with or without the card, that's your prerogative.

Proof is in that denpressure has failed and will fail any practical test. You're so sure of yourself why don't you enlighten us on how much more water a steel block displaces than an aluminium block of same size. It's because you know full well that your idea is a failure, that's my guess. How did that story of yours go again, the one about people believing in unproven ideas?

Ok, let me explain what is really happening in that video.
Now before I go into it, I want you to remember what I said about atmospheric pressure upon any dense mass/object.

When the glass is filled up and the card is placed over the glass then turned upside down, you will notice that there is always a small amount of space at the top of the upturned jar.
This is not a vacuum. It is a very low pressure atmpshere. The massive difference is that the upturned glass botton is now acting as a barrier against the force of atmospheric pressure pushing down, so it can't do it.
This means that the atmospheric resistance under the water in that glass, is much greater than the density (remember this) of the water inside of the glass, so the water cannot be pushed out of the glass unless you were to pierce a hole in the upturned bottom to allow it to happen.

Denpressure, not gravity.

If you make above pressure lower than below resistance, you create  a barrier against any density.
It's the reason why your corned beef won't fall out of the tin to irritation of people. All they have to do when opened, is to pierce the other lid and bingo, atmospheric pressure to your rescue.

Now can you understand it or are you going to deny it?

Quote from: sceptimatic on November 24, 2014, 09:55:18 AM

]The vacuum pulling the water up? are you literally being serious here?
How about explaining this a little.

Here is excerpt from a site with a more detailed explanation:

Quote from: http://www.physicscentral.com/experiment/physicsathome/magicwaterglass.cfm

Isn’t the weight of the water enough to overcome the atmospheric pressure pushing against the card? That’s what most people would think, but if you look at the top of the glass of water (formerly the bottom), you’ll notice a small pocket of air. Actually there isn’t much of an opportunity for air to get into that space, so what we’ve created is a small pocket of low pressure (a place where there really isn’t that many air molecules). There are more air molecules pushing up against the bottom of the note card, creating a higher pressure area compared with the lower pressure area inside the air pocket in the glass. The force from the atmospheric pressure holds the card up and the low pressure zone in the glass prevents the water’s weight from pushing the card down.

So yes, a small volume of low pressure, also known as a (partial) vacuum.

Weirdly that explanation was nearly there, except they're leaving out the killer blow for obvious reasons, because to add the reality in, it destroys gravity.

So again scepti is admitting that atmospheric pressure pushes up.

Quote from: neimoka on November 24, 2014, 10:47:03 AM

Quote from: sceptimatic on November 24, 2014, 10:24:59 AM

Quote from: neimoka on November 24, 2014, 10:19:58 AM

Quote from: sceptimatic on November 24, 2014, 10:15:24 AM

Quote from: neimoka on November 24, 2014, 10:09:08 AM

Pressure is a real thing. Noone has denied that. It just has nothing to do with denpressure. And it doesn't hurt gravity in any way. Unlike the lack of accurate predictions that denpressure theory religion has ever made.

That video proves absolutely 100% what I've been saying about denpressure. You just can't see it and if I explain it to the likes of you, you will still refuse to see it when it slapping you hard in the face. Why?...because your goal is not to see it.

Incorrect. My goal in this thread has been to squeeze enough detail about your denpressure so that it could be meaningfully tested. You don't want that to happen, fine. Then you shouldn't be saying anything about people 'believing in unproven theories', you might get the point, or not.

At least do the courtesy of telling how the scale in vacuum chamber test was wrong in your opinion. It was fake because it wasn't HD or because it destroyed your idea?

Do you know what's happening in the video. If so, explain it. You can yap on all you want about testing this and that. The proof is in your face. It doesn't require figures and crap equations to see that gravity is an absolute pile of crap and denpressure is reality.

What's happening is that the card keeps the water from spreading apart and falling out, because with the card the water acts more like a solid object. It's like a piston in a cylinder. Vacuum forms on the closed top of the inverted glass preventing the 'piston' from leaving the 'cylinder'. That is my understanding of it, knowing that the water won't stay in there if you take the card off. You might deny that ofc and argue that denpressure keeps the water in there with or without the card, that's your prerogative.

Proof is in that denpressure has failed and will fail any practical test. You're so sure of yourself why don't you enlighten us on how much more water a steel block displaces than an aluminium block of same size. It's because you know full well that your idea is a failure, that's my guess. How did that story of yours go again, the one about people believing in unproven ideas?

Ok, let me explain what is really happening in that video.
Now before I go into it, I want you to remember what I said about atmospheric pressure upon any dense mass/object.

When the glass is filled up and the card is placed over the glass then turned upside down, you will notice that there is always a small amount of space at the top of the upturned jar.
This is not a vacuum. It is a very low pressure atmpshere. The massive difference is that the upturned glass botton is now acting as a barrier against the force of atmospheric pressure pushing down, so it can't do it.

okay then.

This means that the atmospheric resistance under the water in that glass, is much greater than the density (remember this) of the water inside of the glass,

What? Atmospheric resistance, which I guess is denpressurese for one or other pressure-like thing, is greater than density? Apples and oranges man. Pressure is force per area and density is mass per volume, neither is greater than the other because they're totally different and unrelated things.

 so the water cannot be pushed out of the glass unless you were to pierce a hole in the upturned bottom to allow it to happen.

This part seems to be true.

Denpressure, not gravity.

If you make above pressure lower than below resistance, you create  a barrier against any density.

What is 'a barrier against density'? Try to not invent your own terminology, this is really difficult to follow.

It's the reason why your corned beef won't fall out of the tin to irritation of people. All they have to do when opened, is to pierce the other lid and bingo, atmospheric pressure to your rescue.

Now can you understand it or are you going to deny it?

I'm inclined to say yes, on both accounts. I kinda sort of get what you're trying to say but it's still bullshit. Yes, pressure differentials can do a lot. But replacing gravity is not on that list.

Can you say what is causing the vac... low pressure atmosphere in the glass when it's turned upside down to begin with - and as a consequence of that, why does the water fall out without the card?? Upside down glass is shielding the water from all directions except from below, where almighty air pressure is pushing it up, why does it fall??

Weirdly that explanation was nearly there, except they're leaving out the killer blow for obvious reasons, because to add the reality in, it destroys gravity.

No, it defies gravity.  There's a difference.

Now when were you going to explain the difference between denpressure and buoyancy?

What? Atmospheric resistance, which I guess is denpressurese for one or other pressure-like thing, is greater than density? Apples and oranges man. Pressure is force per area and density is mass per volume, neither is greater than the other because they're totally different and unrelated things.

Remember when I said that denpressure is a push down force against resistance to that push?

Take a look at the glass and the card covering that glass. The atmospheric pressure is pushing down on the card sticking out from the glass but equal resistance is exerting the same force back under that card. Ok, have we got this?

Now then, the bottom of the upturned glass has a small amount of atmospheric pressure still inside it but it's extremely small compared to what is outside of it. The atmospheric pressure is pushing down on the glass bottom but that's all it can do because it cannot get in to equalise due to the bottom of the glass acting as a barrier.

This means that the amount of water in the glass is under minimal push from the little bit of trapped air inside which is no match for pushing the water out of the glass to overcome the atmospheric resistance of the atmosphere under the card.
The dense water cannot overcome it without that atmospheric push from above.

The apple and orange is a different thing because they are under that push from above so that density of the apple or orange is easily pushed through the resistant atmosphere below.

What is 'a barrier against density'? Try to not invent your own terminology, this is really difficult to follow.

The barrier is air resistance to the density of the water.

Can you say what is causing the vac... low pressure atmosphere in the glass when it's turned upside down to begin with

The lower pressure is because of the small amount of air trapped that cannot push with any force to overcome the larger force below the water due to the glass bottom creating a barrier against that push down pressure from above.

- and as a consequence of that, why does the water fall out without the card??

Because atmospheric pressure is always trying to equalise and if you give it a weak spot by taking away the card, it will simply push into the inside of the glass and force teh water out by a pressure push down as it always tries to equalise. It's about finding the wek point, which the card does not allow.
If you were to drill many holes in the middle of that card, the water would still not fall out because the atmosphere still cannot displace the water to get in and equalise. Drill near the edges and you make the passage easier for the pressure to get in.

Upside down glass is shielding the water from all directions except from below, where almighty air pressure is pushing it up, why does it fall??

Air pressure is not pushing it up. The air pressure is resisting the weak push on the water from the low pressure air inside.