At what height above the earths surface will the value of g be reduced by 36% from the value at the surface radius of the Earth 6400 km?

At what height above the earths surface will the value of g be reduced by 36% from the value at the surface radius of the Earth 6400 km?

Text Solution

Solution : Let `h` be the height at which the value of `g` be reduced by `36%`, i.e., the value of `g` at height `h` is `g' = 100 - 36 = 64%` of the earth's value <br> Hence `g' = (64)/(100)g` <br> Now `g' = (gR^(2))/((R + h)^(2)) = (64)/(100) g` or `(R )/(R + h) = (8)/(10)` <br> or `h = (R )/(4) = (6400)/(4) = 1600 km`