why does earth rotates??

Answer 1

If the earth didn’t rotate on its axis as it does every twenty-four hours, like Mercury, which rotates only a little more than once during its annual trip around the sun, then nearly one half of the earth would be a frozen sub-zero waste, with the remainder a deserted furnace

Answer 2

The rotation is a consequence of the rotational momentum/kinetic energy that existed at the time the formation of the Earth and Solar System.We live in a dynamic universe.(It rotates to conserve angular momentum)

In physics, the angular momentum of an object with respect to a reference point is the measure of the extent to which, and the direction in which, the object rotates about the reference point.

In particular, if the body rotates about an axis, then the angular momentum with respect to a point on the axis is related to the mass of the object, the velocity and the distance of the mass to the axis.

Angular momentum is important in physics because it is a conserved quantity: a system's angular momentum stays constant unless an external torque acts on it. Torque is the rate at which angular momentum is transferred in or out of the system.

Because our solar system came from a collapsed cloud of gas and dust, the tiniest asymetry in the structure of the cloud would cause the entire system to rotate about its center. The rotation caused some of the matter to end up in orbit around the sun - no rotation and all of that matter would have fallen into the sun. Similarly, the condensing of the earth in an asymetric way caused the earth to rotate

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Answer 3

Earth and the rest of our solar system formed within an immense interstellar cloud of gas and dust which had internal motions. As Earth formed, it acquired some of this motion, as did all the other major bodies in the solar system.

Answer 4

My guess would be that using Newtons Laws, initial rotation was probably started as the result of a collision with another planet sized body. not much else would account for the energy required to start spinning something this big, I dont see a source of drag that would cause it to spin through friction.

Answer 5

According to the musical Cabaret, it is due to the effect of money:

"Money makes the world go around,
the world go around, the world go around,
Money makes the world go around,
it makes the world go round."

Answer 6

Hey, I like your handle - very nice. Yashank q, posted later, has your answer.

Answer 7

Just be glad it does!!!