gravity at center of the earth

[AV1611VET]

Would someone please comment on this thread?

 

[sbvera13]

Gravity has no need to directly affect the center of the earth to affect the matter there. It can have an inderect effect through the matter above it, which IS affected by gravity.

Ahem. If you push on one end of a 2x4, both ends of it move at the same time. In the same way, if gravity compresses the earth towards the center, the mass at the center will be compressed by the mass on the outside, because it is all connected. Force is still being applied at some point in the system.

Also, AFAIK, there is gravity at the center of the earth. It's just that it is effectively neutral because it would be equal in all directions.

 

[AV1611VET]

Gravity has no need to directly affect the center of the earth to affect the matter there. It can have an inderect effect through the matter above it, which IS affected by gravity.

Ahem. If you push on one end of a 2x4, both ends of it move at the same time. In the same way, if gravity compresses the earth towards the center, the mass at the center will be compressed by the mass on the outside, because it is all connected. Force is still being applied at some point in the system.

Also, AFAIK, there is gravity at the center of the earth. It's just that it is effectively neutral because it would be equal in all directions.

Okay --- thank you.

 

[paug]

I think that at the center of the earth there is gravity. Here's why i belive there may be. Matter is made up atoms, and atoms are made up of subatomic particles; up qurks, down qurks, gluons, boson's etc... each atom has an atomic mass, thus each patricle has a specific value. (unfortunitlly until the large hardon colider is finshed, mankind will not have proof of the gravitaional values of different materials) This is why some hydrocarbon componds float ontop water.

That having been said, we see things on a 3 deminsonal plane. (x,y,z) So again it only seems logical that atoms would have 3 deminsions and form 3D structers; like a sphear. taking all of this into consideration (along with the fact that our earth has molten lava at it's center) we begin relize that there is a great deal of energy and presure in the planets core. (an inverted example of this would be the bubeles in a soda glass) all the pressure holds the planet togeather squeezing so hard that they cancel eachother out well still maintaing gravetaional energy

What?! How about reading your posts before pressing "Submit"? Seriously. What on earth are you talking about?


PS. Magma is what we find inside the Earth. Lava is like magma, but on the outside.

 

[pgp_protector]

What?! How about reading your posts before pressing "Submit"? Seriously. What on earth are you talking about?


PS. Magma is what we find inside the Earth. Lava is like magma, but on the outside.

Psss That post was about 4 years ago

And the poster --> Last Activity: 15th November 2004 12:15 AM

 

[juvenissun]

Also, Venus and Mars do not have a big magnetic field right now because they are not cooled quickly enough to induce convection in their metallic cores.

Could you explain how does the induction work? What happened if they cooled fast enough? How does the convection begin?

 

[pgp_protector]

Could you explain how does the induction work? What happened if they cooled fast enough? How does the convection begin?

I also doubt that they will respond as they haven't been on for the last 3 years.

 

[juvenissun]

Shouldn't the force of gravity at the center of the earth be zero because all the mass would balance and cancel out? If so, then there should also be zero pressure due to overlaying matter?

I think some a little complicated calculations could answer your (as well as mine) question. But, just think qualitatively this way:

As one gets deeper into the earth, the pressure increases. Assume the earth is uniform in material, the pressure at 2000 km is NOT the double of that at 1000 km, but is less than double. But it is still larger than that at 1000 km. So, the pressure increases non-proportionally (non-linear) as one going deeper into the earth. As you getting closer to the center, the nearby rock only exert small amount of pressure on you. But the higher (shallower) part of the rock still give you the same amount of pressure. There is nothing in between you (at depth) and the shallower rocks to take the pressure (given by shallower rocks) away. So, as you approaching to the center, the pressure only gets higher, even not proportionally higher.

Yes, deeper rock gives you less pressure due to lower gravity pull. But it still adds some pressure to existed pressure. And the total pressure will not decrease with depth.

Now, think, the "rock" gets denser and denser with depth too.

 

[Washington]

There is indeed gravity at the center of the Earth. In fact, it would be pulling at an object there from all directions, which would create the impression of zero gravity.

 

[juvenissun]

Why doesn't Venus have a magnetic field? It is almost the same mass as the earth, is closer to the sun, and has a higher surface temperature. Because the core is NOT liquid? Because it doesn't have a laarge moon to cause tidal heating?

How about the core of Venus is not hot enough due to a quite different planet composition when compared with the earth?

Or Venus could not keep the interior heat long enough due to different planet structure.

Too bad that I don't think we would ever know the answer before we gets to the Heaven.

 

[Wiccan_Child]

The thing about the Earth's gravity is that it isn't quite a "pulling you to the core" type force. The mass in Australia is pulling you to Australia, regardless of where you are. It's just that the mechanics works out that you're effectively pulled into the centre of mass of the system, and for every bit of mass pulling you one way, there's another bit of mass pulling you with equal and opposite force.

In short: there is no net gravity in the Earth's core. The pressure and temperature, however, would be enormous; the Earth's inner core is 5000 - 6000°C, and the surface of the Sun is 6049°C.

 

[MorkandMindy]

The thing about the Earth's gravity is that it isn't quite a "pulling you to the core" type force. The mass in Australia is pulling you to Australia, regardless of where you are. It's just that the mechanics works out that you're effectively pulled into the centre of mass of the system, and for every bit of mass pulling you one way, there's another bit of mass pulling you with equal and opposite force.

In short: there is no net gravity in the Earth's core. The pressure and temperature, however, would be enormous; the Earth's inner core is 5000 - 6000°C, and the surface of the Sun is 6049°C.

Maybe in mid summer but I could hardly feel it today

 

[MorkandMindy]

How about the core of Venus is not hot enough due to a quite different planet composition when compared with the earth?

Or Venus could not keep the interior heat long enough due to different planet structure.

Too bad that I don't think we would ever know the answer before we gets to the Heaven.

I doubt if we'll know by then at the rate this thread is going

 

[Wiccan_Child]

Maybe in mid summer but I could hardly feel it today

You mean you can feel it on other days? I suppose if you lived by an active volcano...

 

[MorkandMindy]

... the Earth's inner core is 5000 - 6000°C, and the surface of the Sun is 6049°C.

Maybe in mid summer but I could hardly feel it today

You mean you can feel it on other days? I suppose if you lived by an active volcano...

One of the Kids made a volcano for a school project and it is nearby, but
I was referring to the Sun. I held my hand up to it today and it wasn't even room temperature.

But we aren't in the Old Earth Creationism forum. Rats.

OK, the Sun's photosphere is about 6000 K, I'd be interested in where you got a figure accurate to one degree Celsius. Mine is a black-body value I use from time to time.

As for the centre of the Earth at present there are a lot of estimates, recent guesses are in the 5,000 to 7,000 range but it will all be sorted out when the 6,378 km long Earth Centre thermometer is ready.

 

[Wiccan_Child]

One of the Kids made a volcano for a school project and it is nearby, but
I was referring to the Sun. I held my hand up to it today and it wasn't even room temperature.

Oh, I see.

OK, the Sun's photosphere is about 6000 K, I'd be interested in where you got a figure accurate to one degree Celsius.

So would I. I thought I shamelessly lifted it from Wikipedia, but that has a value of 5778K, rather than 6049°C. Maybe the Sun cooled down?

Mine is a black-body value I use from time to time.

Black-bodies... *shudder*

As for the centre of the Earth at present there are a lot of estimates, recent guesses are in the 5,000 to 7,000 range but it will all be sorted out when the 6,378 km long Earth Centre thermometer is ready.

I'm sure the LHC, once outdated by the VLHC, could be adapted for that purpose .

 

[cerad]

As for the centre of the Earth at present there are a lot of estimates, recent guesses are in the 5,000 to 7,000 range but it will all be sorted out when the 6,378 km long Earth Centre thermometer is ready.

Thermometer is not going to work. The central diamond will block it.