At what height from the earth does the acceleration due to gravity falls to !!1%!! that of the surface
Acceleration due to gravity on the earth surface, !!g = (GM)/R^2...(1)!!
Acceleration due to gravity a height h above the Earth's surface
!!g^' = (GM)/(R+h)^2....(2)!!
Given that !!g^' = 0.01 g!!
From equation (1) and (2), we will get
!!=> 1/(R+h)^2 = 0.01/R^2!!
Taking squareroot both the sides,
!!=> 1/(R+h)= 0.1/R!!
!!=> 10R = R+h!!
!!=> h = 9R!!
Therefore, option (a) is correct.