Posted by Nicole on .
Calculate the effective value of g, the acceleration of gravity (in meters/second^2), at 5100 km above the earth's surface.

physics 
John,
Isn't "g" constantly 9.8 m/s/s, regardless of height?

physics 
Nicole,
that's what i thought but i put 9.8 and 9.8 in and the answer was wrong. so somehow it's different

physics 
John,
The effective value of g is inversely proportional to the SQUARE of the distance from the center of the earth.
The radius of the Earth is 6378 km. At 5100 km altitude, you are 11,478 km from the center.
g will lowered by a factor (6378/11478)^2
Credit to "drwl"