Since the earth formed rotating on its axis, the centripetal force made it oblate. The further you are from the axis of rotation the larger the effect, so the equator (the furthest point you can be from the axis the effect is greatest.
The lithosphere, the crust and the liquid outer mantel portions of the Earth are flexible. They are flexible enough that centrifugal force caused by the Earth's rotation overcomes the pull of gravity causing the Earth to bulge outward at the equator.
The result is the circumference around the equator is slightly greater than is the circumference around the poles.
Because the earth is rotating. A point on the equator is subject to a centrifugal force which acts in opposition to the gravitational force which is not there at the poles. This means that a freely moving surface, like an ocean, will be 'higher' ( more distant from the centre of the earth) at the equator.
Because Earth rotates the fastest at the Equator, centripetal force tends to pull the faster rotating areas at the Equator out, causing the Earth to bulge there.
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Since the earth formed rotating on its axis, the centripetal force made it oblate. The further you are from the axis of rotation the larger the effect, so the equator (the furthest point you can be from the axis the effect is greatest.
The Earth is not a completely rigid body.
The lithosphere, the crust and the liquid outer mantel portions of the Earth are flexible. They are flexible enough that centrifugal force caused by the Earth's rotation overcomes the pull of gravity causing the Earth to bulge outward at the equator.
The result is the circumference around the equator is slightly greater than is the circumference around the poles.
Because the earth is rotating. A point on the equator is subject to a centrifugal force which acts in opposition to the gravitational force which is not there at the poles. This means that a freely moving surface, like an ocean, will be 'higher' ( more distant from the centre of the earth) at the equator.
Because Earth rotates the fastest at the Equator, centripetal force tends to pull the faster rotating areas at the Equator out, causing the Earth to bulge there.
Because that is how it formed....
24hrs of spin..,