Bufofrog

I am glad your surgery went well. I had a family member have major brain surgery and I know how painful it is. Best wishes on a speedy recovery.

For your math that is correct. Not so much for the rest of the world.

Your source does not agree with NASA and the rest of the scientific community, so I have to disagree with your source. I can see how this article could cause your confusion on the scenarios you introduced. Hopefully you will look at other, reputable sources and not base everything on this one incorrect source. Good luck.

You are misreading the description. First the action and reaction are the equal and opposite, one is not larger. The thrust does not come from the internal pressure of the tote or rocket. The thrust is a reaction of the high velocity fluid exiting the rocket.

That would be a non-traditional interpretation. Typically ambient pressure is the baseline. So a standard pressure gage on the tote would read 5.3 psi, since the tote is pressurized. If the non-traditional interpretation helps you to understand that's fine since it is not incorrect. Why do you think that? I certainly did not say that. No, that is not the rocket effect, I described how rockets work earlier in the thread. No I didn't say that. I never discussed what would happen if we put a hole in the tote with a vacuum. Can first agree on how a rocket achieves a force before we move on? Look at this: How Rockets work.

If the pressure was 20 psi then there would be a pressure of 5.3 psi or 5.3 pounds of force on each inch of the container pushing towards the outside. If you bled off 4 psi of pressure then there would be a pressure of 1.3 psi pushing towards the outside of the tote. If there was a balloon that was filled with air to 20 psi and you let out air to decrease the pressure to 16 psi, the balloon would compress. The effect is not a propeller, it is a rocket effect. The tote would move if you opened the valve (assuming the tote wasn't too heavy to move). The movement is not due to a pressure gradient in the tote, the movement would be due to the reactive force from the mass of air moving out through the valve. If this was done in the vacuum of space the tote would still move because the movement is due to mass of the air leaving the tote and not due to it pushing against anything.

If there is a tote that you close with a cap then you would have a tote that is filled with air. Inside the tote the air pressure would be 14.7 psi (lbs/in^2). Out side the tote the air pressure would be 14.7 psi. This means that inside and outside would have 14.7 lbs of force on each square inch of the tote container. If I pull a vacuum and lower the internal pressure to 12.7 psi, that would mean there would be a 2 lb force on each inch of the tote pushing in on the surface. If the tote was glass nothing would happen, there would simply be a constant force of 2 psi on the glass. If the tote was a pliable plastic the force would push in the walls of the tote. The tote would be compressed in size until the pressure inside the tote was raised to 14.7 psi and then it would be in equilibrium and it would stop compressing. Since the forces are felt on all sides of the tote there would be no force in a particular direction, so the tote would not move. The same thing would happen if instead of a vacuum, if I were to pressurize the tote I would see the same sort of thing, the forces would be uniform in all directions on the inside of the tote. If I were to put a hole in the side of the pressurized tote then the escaping air jet would put a force on the tote that would tend to make it move in the direction away from the streaming air. Gerrard, I thought about your question a bit more and I think I see where you were going. If I were to have a extremely high pressure water in a container and a hose going to a tote and I threw a valve so the water rushed to the container, that would cause a force that would make the container shoot away from the hose entrance due to the pressure gradient in the tote. This is what water hammer is. I have seen some very large pipes 'dancing' due to someone opening a valve too quickly. Hope these replies answer your questions.

Are you asking this question: "If I have a vacuum pump and a tube going to a container, as I pull a vacuum on the container will there be force that moves the container away from the pump?" If that is your question the answer is no. If that is not the question, please try again.

No force is involved it is simply geometry. An explosion spreads out the same way. So does sound. You really need to learn some basic physics and science before you start trying to make hypotheses. Most of your ideas are so wrong it is difficult to try figure out what you are trying to say let alone give you an answer that you can understand.

I am not sure what taming dark matter means. We can measure the mass of dark matter by measuring its effect on a galaxies rotation (not sure how accurately).

Time is a dimension. How's that?

I think many members are probably tired of hearing for the umpteenth time someone saying that they don't believe in climate change because they want to.

Seriously?

How can you make statements about light of you do not know what a photon is? My question was a fair question, I am disappointed that you won't answer it.

Are saying a photon from the sun does not travel to earth? Is this a semantic thing around definitions of terms?