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## Homework Statement

How fast must a satellite leave Earth's surface to reach an orbit with an altitude of 895 km?

## Homework Equations

v = √GM/r

## The Attempt at a Solution

G = 6.67 x 10^-11

M = 5.98 x 10^24

r = (6.38 x 10^6) + (8.95 x 10^5) = 7.275 x 10^6

v = √(6.67 x 10^-11)(5.98 x 10^24)/(7.275 x 10^6)

v = 7404.5 m/s

But this is the speed the satellite needs to stay in orbit. Is this the same speed that it needs to leave the Earth's surface? Do I need to use v = √2GM/r instead to find the velocity it needs to escape the gravitational field at Earth's surface and go into orbit?