Acceleration due to gravity becomes 1/4th. Show it at what height.

Asked by tanaypandey4 | 11th Feb, 2020, 05:22: PM

Expert Answer:

Given g' = g/4 
g =GM/R2 
g' = GM/(R+h)2 
g' is acceleration due to gravity at height h from earth. 
 
g/g' = (R+h)2 /R2 
 
4/1 =  (R+h)2 /R2 
Thus, 
2 = (R+h)/R 
2R = R+h 
R = h 
 
R is the radius of earth i.e. 6400 km 
Hence, the height at which the value of gravity becomes 1/4th is 6400 km. 

Answered by Shiwani Sawant | 11th Feb, 2020, 06:45: PM