Question

Every morning the sun rises every evening the sun sets why does this happen? Why Earth spins on it axis?

Answer 1

Earth spins because of the way it was formed. Our solar system formed about 4.6 billion years ago when a huge cloud of gas and dust started to collapse under its own gravity. As the cloud collapsed, it started to spin. Some of the material within this cloud gathered into swirling eddies and eventually formed into planets. As the planets formed they kept this spinning motion. This is similar to what you see when skaters pull in their arms and spin faster. As material gathered in more closely to form a planet, like Earth, the material spun faster. The Earth keeps on spinning because there are no forces acting to stop it.

Answer 2

Hey that's very simple; a gravitational force acts on every body in the universe. We have many bodies in the universe; for instance we take the solar system. Sun pulls earth towards it and other bodies like other planets also pull towards them which creates a torque that making the earth to spin in its axis.Its must be torque created by forces acting in opposite direction.

Answer 3

Earth spins because it started spinning during its formation, and nothing has stopped it from doing so (yet... dun dun dun dramatic music!). Due to our relative closeness to the Sun, and its immense mass compared with anything else in our solar system, it keeps the Earth in its (approximately) elliptic orbit thanks to gravity - F = G((m1m2)/r^2) - a not-completely-understood property of mass to attract other mass (by not-completely-understood, I mean nobody presently understands exactly why mass has this property, to my current knowledge anyway - but it's a yet to be disproved theory and accepted that it does.) So pretty much just what the others have said.

Interestingly, the small gravitational pull the moon has on Earth keeps it from wobbling all over the place, and maintains its relatively smooth spin. When the moon is eventually pulled from our planet's gravitational pull (which I believe is currently happening at about 4cm a year, or there abouts), the Earth will likely have a substantially more erratic motion.

Answer 4

PS. kukgenius, try not to start answers with 'that's very simple'; things don't become simple or obvious until after we've learnt them ;)

Answer 5

Fewscrewsmissing i agree; thanks for ur suggestion. But i try to give a feel that things are simple rather than saying its complicated.

Answer 6

I would definitely avoid saying that it's very simple if the subsequent explanation isn't right... the fact that the earth is spinning has nothing to do with the gravitational pull of other planets or the sun, and there is zero net torque about the earth's center of mass.

Answer 7

^ due to the other planets, I should say. And replace zero with negligible if you'd like.