Question

A block is being pulled by a rope in a straight line across a horizontal floor which is non frictionless. The rope is pulling on the block with a force of 60N, and the frictional force exerted on the block by the floor is 20N. What is the force with which the block is pulling back on the rope?

Answer 1

60 N

Step-by-step explanation:

We can answer the question by using Newton's third law, which states that:

"When an object A exerts a force (called action) on an object B, then object B exerts an equal and opposite force (called reaction) on object A"

In this situation, we can identify the rope as object A, and the block as object B.

We are told that the rope exerts a force of 60 N on the block: if we apply Newton's third law, therefore, we can say that the block will also exert an equal (60 N) and opposite (in direction) force on the rope.