Question

Andrew is pushing this block to the right across on the floor. Which force in the free body diagram is pointing in the wrong direction?

Question 11 options:

the applied force


friction


the normal force


the weight

Answer 1

Normal force since it's perpendicular to the contact force and should be going up.

Answer 2

the normal force

Step-by-step explanation:

The free-body diagram represents all the forces acting on an object. In this example, there are four forces acting on the box: an applied force, the friction (which always act opposite to the applied force), the weight of the box (which is always downward), and the normal force.

The normal force is the reaction force exerted by the surface on which the box is moving on the box, and this reaction force is always opposite to the force exerted by the box on the surface. Since the latter is downward, it means that the normal force must be upward, so in the diagram it is wrong.