Newton's third law tells us that for every force there is an equal and opposite force. This means that if Anna exerts a force of 20 Newtons on the box, the box exerts a force of 20 Newtons on Anna.
The magnitude of the force exerted by the box on Anna is 20 newtons.
Explanation:
It is given that, Anna needs to move a box of paperback books across the room. If she applies a force of 20 newtons to the box. We need to find the magnitude of the force exerted by the box on Anna.
The force exerted by the box on Anna is 20 newtons but it acts in the opposite direction as per Newton's third law of motion. The third law of motion explains the impact of forces i.e. action and reaction force.
So, the magnitude of the force exerted by the box on Anna is also 20 newtons. Hence, this is the required solution.
