A father is pulling his child on a sled in the snow. According to Newton’s Third Law, the force the father exerts on the sled is equal to the force the sled exerts on the father but opposite in direction. How is it possible that the father can pull the child and sled forward?

Question

A father is pulling his child on a sled in the snow.  According to Newton’s Third Law, the force the father exerts on the sled is equal to the force the sled exerts on the father but opposite in direction.  How is it possible that the father can pull the child and sled forward?

anonymous · Answer

Consider friction forces of the sled smaller than the friction forces of the father over the snow.