At what distance above the surface of earth, the gravitational force will be reduced by 10%, if the radius of earth is 6370 Km.
Gravitational force on the earth surface,
FGs=GMmR2
Gravitational force at a height 'h' above,
FGh=GMm(R+h)2
G.T. FGh=90100(FGS)
⇒GMm(R+h)2=910(GMmR2)
⇒R+h=√109(R)
⇒6370+h=3.1623(6370)
⇒h=0.162×63703=344 km