How?

[doowdniw]

No fat jokes, please. This is a science thread. Or something.

I was thinking intellectually. Fat people actually float better than lean, because less dense.

 

[sweepthefloor]

it's so complicated and it must be the stress-energy that pulls me down when i am so sad. why do helium balloons float away when you let them go?

 

[Freudian_Slit]

it's so complicated and it must be the stress-energy that pulls me down when i am so sad. why do helium balloons float away when you let them go?

Buoyancy. There is slightly more air pressure below the balloon than above, so the net buoyant force on the balloon is upward. How much the balloon accelerates depends on the difference in weight of the balloon to the air it displaces.

 

[sweepthefloor]

Buoyancy. There is slightly more air pressure below the balloon than above, so the net buoyant force on the balloon is upward. How much the balloon accelerates depends on the difference in weight of the balloon to the air it displaces.

it's got to have something to do with the gas, right?

 

[Freudian_Slit]

it's got to have something to do with the gas, right?

Yup. A balloon filled with helium, which is less dense than air, will weigh less than the atmosphere it displaces. So helium balloons rise. But a balloon filled with air will weigh approximately the same as the air it displaces (slightly more due to the weight of the balloon itself). So a balloon filled with air falls slowly and tumbles with the breeze.

 

[Libsam]

Da man. Spot on. :thumspup:


It's someone I don't know but on my facebook for a different reason.

I don't want to argue, I didn't post anything, but want to give him a one liner only that would make him think of it differently.

He's quite convinced beyond doubt that the earth is flat. And he's a healthcare professional mind you. Educated...

Nailed it! I'm motherfucking Sherlock Holmes, bro!
(working on my Stew Pidgin)

Maybe try this: We can observe from earth that other planets are spheres, so is earth the only flat planet in our solar system?


p.s. Nursing is just a technical degree you get at a university. (That really pisses em off.)

 

[Colonel Hogan]

I was saying how do we know the pull down force is "gravity" and not mere atmospheric pressure where the weight of the atmosphere is pushing things down.



The one exerted by larger masses than Earth like the Sun.

The mass of the earth is far greater than the mass of the atmosphere or, for that matter, the mass of your own body. Therefore, the gravitational pull of the earth's mass is the far greater force acting upon you.

The gravitational forces exerted by the much larger Sun, other planets, and other stars within our galaxy upon the earth are mitigated by the EVEN GREATER vast distances of those bodies FROM the earth relative to the gravitational force they are exerting.

 

[Hypoxia]

So far, nothing in this thread has explained why the Aussies don't fall off.

Kangaroo shit is good glue. Walk in it; you can then climb walls like a housefly or spider. That's why Oz beer is as it is.

You can't land a helicopter at the North Pole because the Earth is spinning 1,000 MPH and as soon as it touched down, it'd just take off again.

No problem; reverse the rotor pitch. Better yet, go by gyroplane.

But compared to quantum froth, none of this matters.

 

[Colonel Hogan]

Just say "OK smart guy, explain electricity."

Best one I've seen.

Electrons in atoms can act as our charge carrier, because every electron carries a negative charge. If we can free an electron from an atom and force it to move, we can create electricity.

Consider the atomic model of a copper atom, one of the preferred elemental sources for charge flow. In its balanced state, copper has 29 protons in its nucleus and an equal number of electrons orbiting around it. Electrons orbit at varying distances from the nucleus of the atom. Electrons closer to the nucleus feel a much stronger attraction to the center than those in distant orbits. The outermost electrons of an atom are called the valence electrons, these require the least amount of force to be freed from an atom.

Using enough electrostatic force on the valence electron–either pushing it with another negative charge or attracting it with a positive charge–we can eject the electron from orbit around the atom creating a free electron.

Now consider a copper wire: matter filled with countless copper atoms. As our free electron is floating in a space between atoms, it’s pulled and prodded by surrounding charges in that space. In this chaos the free electron eventually finds a new atom to latch on to; in doing so, the negative charge of that electron ejects another valence electron from the atom. Now a new electron is drifting through free space looking to do the same thing. This chain effect can continue on and on to create a flow of electrons called electric current.

https://cdn.sparkfun.com/assets/9/5/6/1/4/519fcd42ce395f804c000000.gif

https://learn.sparkfun.com/tutorials/what-is-electricity