Acar is moving east along a straight, level road at a constant velocity. which forces form an action/reaction force pair?

a. the force of the tires against the road and the force of the road on the tires
b. the weight of the car and the force of the road pushing up on the car
c. the force of the engine on the car and the force due to friction on the car
d. the normal force on the car and the force of the car pulling on earth

A.the force of the tires against the road and the force of the road on the tires

Explanation:

The action/reaction force pair are the forces described in Newton's third law, which states that:

"when an object A exerts a force on object B, object B exerts an equal and opposite force on object A"

Therefore, this law is applied if we are considering two objects only. Let's analyze each statement:

A.the force of the tires against the road and the force of the road on the tires  --> TRUE. In fact, object A is the tires, while object B is the road, so this statement satisfies Newton's third law.

B.the weight of the car and the force of the road pushing up on the car  --> FALSE. In this case, the two forces are not an action/reaction pair, because the weight of the car is the force exerted by the Earth (object A) on the car (object B), so the reaction force would be the gravitational attraction exerted by the car (object B) on the Earth (object A).

C.the force of the engine on the car and the force due to friction on the car  --> FALSE. In this case, the action is the force the car (object A) exerts on the engine (object B), so the reaction should be the force that the engine (object A) exerts on the car (object A).

D.the normal force on the car and the force of the car pulling on Earth -- FALSE. The normal force is the force that the road (object A) exerts on the car (object B), so the reaction should be the force that the car (object B) exerts on the road (object A).