Question

A 48-kg woman pushes a 12-kg grocery cart with a force of 24 N. What is the magnitude of the force that the grocery cart exerts on the woman?
A. 96 N 
B. 24 N 
C. 12 N 
D. 6.0 N 

Answer 1

The correct answer is B. 24 N.

To figure out the exact force the cart exerts on the woman, we have to use Newton's third law of motion.  Newton's third law of motion states that every action has an equal and opposite reaction. This means that if object  1 exerts a force on object 2 , object 2 will exert an equal but opposite force on object 1.

This law allows us to ignore the masses of the chart and the women and focus on the  pairs of forces the woman and the chart apply to each other.  Since the woman exerts a force of 24 N on the chart, the chart will exert a force of 24 N on the woman.

The correct answer is B. 24 N.