A horse pulls upon a wagon, but according to Newton’s third law the wagon pulls back with an equal and opposite force upon the horse. Use a free-body diagram and show all the involved forces.

i posted this question before but i still don't get it. Could someone explain what forces are involved in this problem?

1 answer

Netforce=mass*acceleration.

If there is not acceleration, then net force must be zero. How can it be zero if something is pulling? ANS: something (friction?) is pulling back equal and opposite, so there is zero acceleration.