Question 4

This question has Statement 1 and Statement 2. Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement 1: If you push on a cart being pulled by a horse so that it does not move, the cart pushes you back with an equal and opposite force.

Statement 2: The cart does not move because the force described in statement 1 cancel each other.

Solution

Solution & Explanation

1. Evaluate Statement 1 using Newton's Third Law

When you push on a stationary cart with a force ($$\vec{F}_{\text{you on cart}}$$), the cart simultaneously exerts a force back on you ($$\vec{F}_{\text{cart on you}}$$). According to Newton's Third Law of Motion, every action has an equal and opposite reaction:

$$\vec{F}_{\text{you on cart}} = -\vec{F}_{\text{cart on you}}$$

Since these two forces are equal in magnitude and opposite in direction, Statement 1 is true.

2. Evaluate Statement 2 (Why the Cart Does Not Move)

An object's state of motion is determined strictly by the net force acting on that single body. Action and reaction forces never cancel each other out because they act on two entirely different objects:

The action force acts on the cart.
The reaction force acts on you.

Because these two forces are applied to different objects, they cannot cancel one another out. The cart remains stationary because the forward pull of the horse is perfectly balanced by other external forces resisting it on the cart itself. Therefore, Statement 2 is false.