Math BOBPURSLEY HELP HELP HELP HELP
posted by Dwayne on .
Law of Gravitation Find an expression for the magnitude of the initial velocity that a projectile must possess in order to leave the earth when air friction is neglected.
The gravitational constant for g is, G = 6.67428*10^11 m^3 Kg^1 s^2
Please answer the question fully and please give any helpful websites, thankyou.
Also I know calculus.

Then set the initial KEnergy equal to the potential energy at the surface of EArth.
1/2 mv^2= GMe*m/re
solve for escape velocity, v 
v^2 = 2Mg/r + (u^2 2Mg/d )
Is that right 
Why did you make it so complicated?
1/2 m v^2=GMe m/re
v^2= 2GMe/re
take the square root of each side.