Final answer:
The action-reaction pairs according to Newton's third law are: the horse pulling on the cart and the cart pulling on the horse, and the horse pushing on the road and the road pushing on the horse.
Step-by-step explanation:
According to Newton's third law of motion, for every action, there is an equal and opposite reaction. When examining the forces involved with a horse pulling a cart, we can identify the action-reaction pairs by looking for forces that are equal in magnitude, opposite in direction, and act on different objects. In this case, we have the following pairs:
- The force of the horse pulling on the cart (1) is the action force, while the force of the cart pulling on the horse (2) is the reaction force.
- The force of the horse pushing on the road (3) is the action force, while the force of the road pushing on the horse (4) is the reaction force.
These pairs of forces meet the criteria of Newton's third law, as they are equal in strength, opposite in direction, and act on different systems: the horse and the cart, and the horse and the road respectively. These pairs do not cancel each other out because they are acting on different objects, aligning with the important features of Newton's third law as mentioned in the reference material provided.