Posted: Mar 19, 2012 6:18 pm
questioner121 wrote:
One thing that doesn't seem quite right is the gravity of the earth. If the gravity of the earth is zero at the centre of the earth and it gets weaker as you go below the surface of the earth, ...
The problem your present clearly stems from a lack of education and/or understanding.
Others gave a reply, here are some external links ... with math n' sh|t.
http://hyperphysics.phy-astr.gsu.edu/hb ... thole.html (take special note of the 2nd diagram)
http://wiki.answers.com/Q/Would_there_b ... _the_earth
http://en.wikipedia.org/wiki/Center_of_mass#Astronomy (important to know why the sun cannot orbit the earth)
http://www.physicsforums.com/showthread.php?t=203955 (good answers starting at post 9)
questioner121 wrote:
... how did it come together and stay together given that it was rotating from the beginning and actually rotating faster?
The rotation of the earth was not always the same and it wasn't even a gradual descent from fast spinning to slower spinning. At first the earth did not even had a moon.
http://www.youtube.com/watch?v=e1-F4lxJPo0 (long video but worth to watch)