A body weighs 180 N on the surface of earth (Radius=R). How much does the body weigh at a height R2 above the surface of earth?
80 N
120 N
160 N
140 N
On the surface of earth W=mg=m.GMR2
At a height R2 above the surface of earth
W1=mg1=mGM(R+R2)2=49GMmR2=4W9
⇒W1=49×180 N=80 N