Why does the Earth revolve around itself?

Answer 1

In space, EVERYTHING spins; fast or slow, everything rotates. The physical law of conservation of angular momentum enforces that. So it would be somewhat strange if the Earth itself didn't rotate. (But if the Earth didn't rotate, we wouldn't be here to notice the fact!)

And the "axis" is just the centerline of the rotation, so everything that spins - and that's everything! - rotates "around its own axis".

All of the planets and stars rotate; the Sun rotates once every 26 days, Jupiter in 10 hours or so, Mars in 24 hours 40 minutes. Venus is sort of the "odd man out"; it hardly rotates at all, and rotates in the opposite direction of all the other planets of our solar system.

So, what CAUSED the rotation? There are dozens of things that might have caused it, and we don't know which ones - or in what magnitude - might have played a role.

Foremost, every atom of the cloud of gas and dust that condensed 5 billion years ago had its own velocity. So when they all came together, there would have been some overall rotation of the gas cloud. When the cloud's own gravity caused it to form the Sun and the planets, each eddy in the cloud would have included its own component of the overall rotation. The proto-Earth would have been rotating regardless of what else happened later.

Another big factor would have been the collision between the proto-Earth and another body in the solar system back when the solar system was still very young. We believe that the "other body" was of nearly planetary size, perhaps even as large as Mars. If the collision were't precisely centered - which would have been astonishingly unlikely - then the impact could easily have set the Earth spinning, or changed the rate of the spin. It's at least plausible that the 23 degree angular tilt of the Earth's rotation as compared to the plane of the solar system was caused by this collision. The debris from this collision

Add in the "Early Heavy Bombardment" period in Earth's history, as most of the stray bodies of the solar system crashed into each other for the first billion or so years. So you see, there are any number of causes that contributed to the Earth's spin.

Answer 2

The Sun.

Also, the center of the Milky Way galaxy, as the Sun itself revolves around the center of the galaxy.

Answer 3

The Earths rotation has to deal with its orbit around the Sun.

Answer 4

It doesn't it goes around the sun.