the height above the surface of earth where g decreases to 9% of its maximum value on earth surface is.(radius of earth 6400 km)

Dear anand s

g=G Me/(Re +h)²

 wher h is hight from earth surface

value of g on earth  surface is for h=0

g1=G Me/(Re )²

 

so we need to find g such that

 g=.09 g1

G Me/(Re +h)²   =.09G Me/(Re )²

or Re =.3 (Re+h)

h=7Re/3

 

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