Is the earth flattened

[einsteinsdog]

Is the earth considered to be flatter at the poles because of centripetal forces?

[sddsddean]

Yes, its an oblate spheroid.

[mibn2cweus]

The tendency of an object to travel in a straight line is what causes the Earth to bulge slightly, especially around the Equator where the spinning velocity is the greatest, a little over 1000 miles per hour.

Since the velocity of rotation is less the nearer we get to the axis of rotation, the north and south poles, there is less outward momentum. Earth is flattened more by gravity where rotational velocity is less, nearer to the poles, than that nearer to the Equator.

Gravity is the centripetal force that causes the Earth to maintain a nearly spherical shape.

[JudgeJ]

The earth is flattened at the poles (or, to be more pedantic, it bulges at the equator) because of centrifugal force. This is the force that forces objects towards the edge of something which is spinning, rather in the way that your laundry gets thrown to the outside of a spin drier.

Centripetal force draws matter towards some point acting as a centre (i.e. tends to keep the earth together as a perfect sphere) and thus acts counter to the centrifugal force.

[Hippy]

Centrifugal Force does not exist!

Stand on the rim a rotating merry-go-round and you can feel something pushing you off the edge; you have to hold on to stop yourself whizzing into the rest of the fairground. It must be real! No. The merry-go-round has imparted acceleration to you and inertia dictates that you travel in a particular direction in a straight line. That would carry you into the field. You have a desire to maintain your frame of reference as the merry-go-round so grab hold of the pole. The pole exerts a real centripetal force on you and it is that which you feel and because your frame of reference is the rotating disc you interpret this pull towards the centre as a force trying to fling you outwards.

The centripetal force acts at right angles to your velocity towards the centre of rotation. As such it alters your acceleration towards the centre of rotation. Without this force you would (other obstacles neglected) fly out in a straight line, being a tangent to the edge of the rotating disc. This is your inertia, the momentum you posses due to the acceleration you absorbed up to the point you were released from the centripetal force.

See HERE for a bit more on this.