Shape of the Earth

[Mohit Pandey]

What is the exact name given to the shape of the Earth?
I read somewhere that poles are not in proper shape. Please tell me about it also.

[Jay-qu]

I am not sure what you would call it either, its a sphere that bulges at the middle, ie its equitorial diameter is larger than its polar diameter. This is because of the spin

[ronthepon]

An oblate spheroid or something of that sort.

Umm... yeah. Here it is.

http://regentsprep.org/Regents/earth...ion/oblate.cfm

[Boerseun]

Squashed ball?

[arkain101]

a flat dimension stuck in a gravity curve in space-time?


The poles are not at the very top and bottom. They fluctuate posistion, based on the action of the core inside the earth.

The magma core is massive and a large generator of magnetic field.

According to evidence the magnetic field flips poles from time to time (Tens of thousands of years -time to time-)

[Turtle]

Originally Posted by arkain101

a flat dimension stuck in a gravity curve in space-time?


The poles are not at the very top and bottom. They fluctuate posistion, based on the action of the core inside the earth.

The magma core is massive and a large generator of magnetic field.

According to evidence the magnetic field flips poles from time to time (Tens of thousands of years -time to time-)

NO; it is not flat.
NO; this only refers to the magnetic poles, not the geographic poles.
NO; the core is not magma, the mantle is.
Yes; the magnetic poles flip and wander, but NO, this has nothing to do with Earth's shape.

[Turtle]

Originally Posted by Jay-qu

I am not sure what you would call it either, its a sphere that bulges at the middle, ie its equitorial diameter is larger than its polar diameter. This is because of the spin

Earth's spin (rate of rotation) has little to do with the oblate speroid shape of Earth. The root cause is tidal bulge from the gravitational pull of the Moon.

Originally Posted by exo.net

There are also tides in the solid earth. The tidal bulge is about 1 meter high. The moon pulls up this tidal bulge on the earth, there is a time delay between the pull of the moon and the time when the tidal bulge reaches its maximum height. During this time the rotation of the earth carries this tidal bulge around the planet in the direction of rotation.

http://www.exo.net/~pauld/physics/ti...levolution.htm
The calculus of tidal bulging:
http://scienceworld.wolfram.com/phys...dalTorque.html

The Sun also effects a tidal bulge on Earth, but I'm still tracking down the amount. BBS

Addendum:

Originally Posted by geography.about.com

The moon, which is approximately 240,000 miles (386,240 km) from the earth, exerts a greater influence on the tides then does the sun, which sits 93 million miles (150 million km) from the earth. The strength of the sun's gravity is 179 times that of the moon's but the moon is responsible for 56% of the earth's tidal energy while the sun claims responsibility for a mere 44% (due to the moon's proximity but the sun's much larger size).

http://geography.about.com/od/physic...hy/a/tides.htm

[arkain101]

NO; it is not flat.

joking

NO; this only refers to the magnetic poles, not the geographic poles.

thats what I said or at least meant.

NO; the core is not magma, the mantle is.

I stand corrected. Center of the earth creates magnetic field right? I realise now I am not sure what section exactly.

Yes; the magnetic poles flip and wander, but NO, this has nothing to do with Earth's shape.

Agreed. But they change posistion as I said.

[Turtle]

Originally Posted by arkain101

joking

Oh.

Originally Posted by Arcane

I stand corrected. Center of the earth creates magnetic field right? I realise now I am not sure what section exactly.

More or less correct; the exact dynamics remain under scientific study and debate.

Originally Posted by Arkane

Agreed. But they [magnetic poles]change posistion as I said.

Just nod & smile.

[Turtle]

Originally Posted by Boerseun

Squashed ball?

More like a squishing ball, and not to be confused with a squash ball.