[问答题]
When an object falls freely under the influence of gravity there is a n/ m28robxd ujc/.9ga regbq (6t efd0sj1 rfl l)v)n1-ft force mg exerted on it by the Earth. Yet by Newton’s third la 1ql(6detfv1 gsnjfbl-)fr0) w the object exerts an equal and opposite force on the Earth. Why doesn’t the Earth move?
