A horse pulls a cart along a flat road. They start from rest and as time goes on their speed increases. Consider the following four forces:

The force of the horse pulling on the cart;

The force of the cart pulling on the horse;

The force of the horse pushing on the road

The force of the road pushing on the horse.

Which of the following statements is true concerning these forces?

Force 2 exceeds force 4.

Force 2 is less than force 3.

Force 3 exceeds force 4.

Forces 1 and 2 cannot have equal magnitudes.

Force 1 exceeds force 2.

Forces 1 and 2 cannot have equal magnitudes.

Force 1 exceeds force 2.

Explanation:

Numbering the given statements:

The force of the horse pulling on the cart. The force of the cart pulling on the horse. The force of the horse pushing on the road. The force of the road pushing on the horse. When a horse pulls a cart along a flat road starting from the state of rest, the horse applies a force on the ground in downward-back direction diagonally and as its reaction it moves forward. During this action there is also a reaction force by the road on the horse which exceeds the force of the horse on the ground and as a result the horse moves forward. For pulling the cart the horse applies the force on the cart in the forward direction and as a reaction the cart applies a force on the horse in the backward direction which is less than the force of the horse on the cart resulting in the forward motion of the cart along with the horse.