Scepti, honest question, I kinda have my head around your model, atmoplanic pressure holds us down like a sort of inverse boyancy (if I'm wrong please clarify.)
Yep you're sort of on the right track.
Why do I weigh the same in my house under a roof?
If you understand the inverse buoyancy then you also understand that your house is not a sealed unit. It means that atmosphere will fill it rather than crush it.
However, you can create a low pressure inside your house by expanding molecules via heat by body count and/or central heating/fire.
Think of this as creating an air lock under water.
Can you grasp what I'm saying?
The way I understand it it should be like water pressure, e.g an exposed diver would be crushed by the pressure that a submarine can reach, however in the submarine the passengers do not feel the pressure as it is all exerted on the hull. When I get in my car or my house why don't I feel a reduction in weight due to a solid roof.
The submarine is a sealed container of air pressure. It has a hull strong enough to withstand the external water pressure exerted upon it.
The hull as well as the internal air pressure are enough to stop if being crushed as long as the right depth is adhered to.
As for your car and house. Your car and house, as I said earlier, are not sealed units. They equalise the pressure, almost, unless you either accelerate in open top or near sealed environment.This changes the atmospheric pressure wave against you.
Open top would naturally friction push your body and near sealed inside a car under acceleration would build compression upon your body.
To further clarify, if I am at 10 metres depth in a pool, I can feel a very large amount of pressure on my body, if I then climbed into a 2m x 2m water tight box filled with water, the pressure on me is only what the box is capable of holding as the box takes all of the pressure of the pool and we are only left with the pressure of the say 2m × 2m box.
Assuming you could miraculously breathe and the box is strong enough to resist the pressure, then you will be fine.
Can the pressure from the atmoplane pass through our solid objects? Or am I totally missing something here.
This is where most people fail to grasp and this is actually key to understanding atmospheric pressure upon density/mass.
The answer is, it can pass through what you assume are solid objects and cannot pass through some solid objects.
The mere fact that we assume solid to be solid, is only a small portion of the truth.
This is why porosity comes in. This is why atmospheric pressure acts on any object that is placed into it and we know all objects are placed into atmosphere from bottom up, which is also something to keep in mind.
A brick and a bar of gold of equal size.
You know which one feels heavier.
You're told that gravity acts on the mass of the gold and that's why it's pulled down harder, yet regardless of this, you're still told that both objects fall at 9.8m/s and it's accepted.
The reality is far simpler.
The brick is porous and the gold is not, or very close to not.
This means that the brick has most of its make-up already taken up by the atmosphere. So that atmosphere inside of the brick already renders most of that brick make-up as actual atmosphere with bonded elements (clay mix, etc).
Now think about this.
Before your brick became this porous, it was much more dense. It was full of water and clay mix, etc.
It repelled the atmospheric pressure upon it. It meant it could resist it or push against the push of atmosphere.
You can feel the difference in a fresh made brick and a ready to use brick.
To make that brick porous like we see, the bricks are dried out. Water is expelled by expansion and replaced with atmosphere, making the brick much less dense and much more porous, meaning much less atmospheric pressure pushing the actual solid elements that make it due to it being already saturated with atmosphere.
Now to the gold bar.
It's what we term as solid. It's as close to solid as we can get. It repels almost all atmospheric pressure, meaning all of that pressure is pushing on the entire area of that gold bar which is resisting that pressure.
You feel the difference in strength of push by holding both.
You measure the scale weight by man made scale plate etc, with that object placed upon/in it.
There's a reason why a sponge is as light as it is.
This should be obvious now.
Grab a sponge and squeeze it as tight as humanly possible. Use a machine to squeeze it tighter and tighter until it's almost impossible to squeeze it any more.
What do you have?
You have a sponge (say face size) is now the size of a pea or smaller. That's how dense it became and that's all that the atmospheric pressure is actually pushing against.
So if you let the sponge expand, you know that it's density is only acted upon by a tiny amount which makes it feel as light as it does.
Try that with a gold bar and all you do is misshape it. You do not crush it down, so therefore you are looking at something that repels atmospheric pressure to such an extent that it becomes super heavy in your hand and weighs as a much higher measurement on a scale plate.
If you're as intelligent as I think you are then you will try and grasp it and not try to play games like most do.
The ball is in your court.