# Gravity Problem Help

#### bengaltiger14

I need to find the value of acceleration of gravity 3000 miles above the earths surface. I figured 3000 miles = 4.83 x 10^3 meters. Mass of the earth equals 5.98 x 10^24kg. I used the equation:

g= GM/r^2 and get 17.1 m/s^2. This is too high a value. I don't think I am using the correct distance in my calculation. Any help Please?

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#### bengaltiger14

Ok, I think I got is. I need to add the radius of the earth which is 11.2 x 10^6 meters to the 3000 miles and the acceleration = 3.17 m/s^2 correct??

#### BobG

Homework Helper
bengaltiger14 said:
Ok, I think I got is. I need to add the radius of the earth which is 11.2 x 10^6 meters to the 3000 miles and the acceleration = 3.17 m/s^2 correct??
Yes, it is correct (although I think you meant 3000 miles {4828 km} plus the radius of Earth {6378 km} equaled 11.2 x 10^6 meters.)

"Gravity Problem Help"

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