Is gravity a push or a pull?

[razeontherock]

Reminds me of this:

YouTube - ‪Wile E. Coyote vs Road Runner‬‏

So physics can teach me to fall off my chair?

 

[Wiccan_Child]

I dunno that's just the way it was explained to me by physicists on the AskScience section of Reddit. Just because you're moving toward the earth doesn't mean you're accelerating. It just means you and the earth are both taking straight lines through space that happen to intersect. And when your paths do intersect, the earth tends to change your direction and momentum (sometimes with gruesome results, depending on how far away you were when you started falling toward the earth)

If there was no atmosphere, then if I jumped out of a plane*, I'd accelerate towards the Earth at what amounts to 9.81 m s[sup]-2[/sup]. I'm falling down the Earth's gravitational well - and, conversely, the Earth is slightly rolling down my own body's exceedingly shallow gravitational well. Certainly I could be moving towards the Earth without accelerating, but ultimately the Earth has mass, this mass warps space, and this warped space accelerates me towards the Earth. I don't know who told you that you gravity isn't acceleration, but... they're wrong!

*Yes, planes can fly without an atmosphere

 

[razeontherock]

Ok so physics can't teach me to fall off my chair and I'm on my own for that one.

How can a plane fly w/ no atmosphere; lift isn't a reaction to it?

 

[Wiccan_Child]

Ok so physics can't teach me to fall off my chair and I'm on my own for that one.

How can a plane fly w/ no atmosphere; lift isn't a reaction to it?

It was a joke Planes fly by moving through the air, creating a differential pressure on their wings, lifting the whole thing up.

 

[Jazer]

*Yes, planes can fly without an atmosphere

There would be no oxygen. Can you fire a gun if there is no atmosphere?

 

[Wiccan_Child]

There would be no oxygen. Can you fire a gun if there is no atmosphere?

Again, it was a joke. Hence the smilie. Can you fire a gun with no atmosphere? Sure, so long as the explosive charge doesn't rely on atmospheric oxygen (maybe an internal oxygen tank), or if the gun doesn't rely on combustion (sonic weaponry, laser weaponry).

 

[razeontherock]

Ammo w/ an internal oxygen tank? A scuba diver!

 

[Saving Hawaii]

There would be no oxygen. Can you fire a gun if there is no atmosphere?

With an oxidizer, yes.

 

[Saving Hawaii]

It was a joke... Planes fly by moving through the air, creating a differential pressure on their wings, lifting the whole thing up.

What about spaceplanes? Those function with no atmosphere and a heck of a lot of gravitational influence.

 

[Saving Hawaii]

Ammo w/ an internal oxygen tank? A scuba diver!

Nah... more like a paintballer. That's exactly what they use.

 

[Wiccan_Child]

What about spaceplanes? Those function with no atmosphere and a heck of a lot of gravitational influence.

When they're in space, there's little gravity. When there's strong gravity, they're close enough for the atmosphere to provide lift. And, of course, they have pretty hefty rockets for when they need that extra boost.

 

[razeontherock]

When they're in space, there's little gravity. And, of course, they have pretty hefty rockets for when they need that extra boost.

So to be serious, they do operate on a different principle from atmospheric lift?

 

[Wiccan_Child]

So to be serious, they do operate on a different principle from atmospheric lift?

The same principle at first, generating atmospheric lift to go up in the air. But eventually there's too little air to generate sufficient lift, which is where the big rockets come in - normal planes use their engines to move forward, not up, while these spaceplanes use their engines to do both.

 

[Jazer]

Ammo w/ an internal oxygen tank? A scuba diver!

Actually a bullet is pretty air tight. The gun power already has all the oxygen needed for an explosion. That leaves the question in space what would slow down or stop the bullet.

If you put a bullet in a fire the bullet will stay and the shell will fly. My son left some bullets under the couch and the cleaning lady freaked out thinking the vaccum cleaner could have fired one of the bullets.

I do not worry to much about guns, it's the bullets I worry about

 

[AV1611VET]

Does a vacuum cleaner work in outer space?

 

[razeontherock]

@ post #33: So my intuition was right - thanks!

 

[razeontherock]

Does a vacuum cleaner work in outer space?

Only with hazard pay.

 

[Jazer]

Does a vacuum cleaner work in outer space?

I don't think so, it is difficult to get a cleaning lady to work here.
I think it would be impossible to find one in outerspace.
My younger son wants a new gaming computer,
maybe I can get some work out of him.

 

[AV1611VET]

I don't think so, it is difficult to get a cleaning lady to work here.

 

[Hespera]

Vaccum does not need cleaning.