Something amazing to tell you concerning physics and motion

[bdeg]

Originally Posted by Baby Lee

11.186 km/s. More precisely sqrt(2GM/R), where G-gravity, M-mass, R-radius.

I believe the question was how fast does it need to be fired horizontally to enter orbit(maybe the phrase was 'escape gravity').

now that would be an impressive calculation(with wind resistance please)

[Baby Lee]

Originally Posted by bdeg

I believe the question was how fast does it need to be fired horizontally to enter orbit(maybe the phrase was 'escape gravity').

now that would be an impressive calculation(with wind resistance please)

That is the horizontal calculation [sans wr]. Like said above, at that speed, the curvature of the earth recedes under you at the same rate that gravity pulls you down to earth [that's why R-radius is integral to the equation].