質問: the work done in slowly lifting a body from surface to height r is twice the amt. of work done in lifting the same body from earth surface to height h . find the height h.
回答: dear student work done will be stored as potential energy 2[ -gmm/(r+h) + gmm/r ]= -gmm/2r + gmm/r 3gmm/4r = gmm/(r+h) 3h = 4r h = r/3 regards arun (askiitians forum expert)