Diaisa asked:

How long has the Earth been spinning? Will it rotate forever? What would happen if it stopped
suddenly?

1) About 4.6 billion years (4600000000 years).

2) No — the sun will eventually expand and consume the earth — in about another 5 billion years.

3) It won't — the amount of energy needed to do this is far too large.

Tim Sprod

1) Billions of years, anyway... about from the origin of the solar system... but I don't remember the
exact number. Look it up.

2) No. Nothing lasts forever. Eventually our sun will turn into a red giant and swallow up and vaporize
the earth. It will stop rotating at that point, since it won't exist. However, don't hold your breath... that's
another at least several hundred million, and probably a few tens of billions, years off.

3) On this, take a look at HG Wells "The man who could work miracles" for a nice graphic description.
Imagine a sphere turning very fast with lots of little thingies on it. You stop the sphere... what
happens?

Steven Ravett Brown