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## Main Question or Discussion Point

Hi guys!

I want to ask something about escape velocity.

I know the definition of EV "escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero"(wikipedia).

Can we approach the problem by equalling the attractive force to the centrifugal force. I tried to find the the V in this way but I found the V [tex]\sqrt{2}[/tex] times smaller. What is wrong with it?

mv^2/r = GmM/r^2

V=[tex]\sqrt{GM/r}[/tex]

sorry about my poor English.

I want to ask something about escape velocity.

I know the definition of EV "escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero"(wikipedia).

Can we approach the problem by equalling the attractive force to the centrifugal force. I tried to find the the V in this way but I found the V [tex]\sqrt{2}[/tex] times smaller. What is wrong with it?

mv^2/r = GmM/r^2

V=[tex]\sqrt{GM/r}[/tex]

sorry about my poor English.