Question

When Mrs. Knight drops her briefcase and it lands on the floor, what is the reaction force to the action force of the briefcase on the floor?

a) The attraction of Earth for the briefcase
b) The force of air on the sides of the briefcase
c) The force of the floor on the briefcase
d) The force of friction between the briefcase and the floor

Answer 1

The reaction force to the action of the briefcase on the floor is the force of the floor on the briefcase, adhering to Newton's Third Law of Motion.

Step-by-step explanation:

When Mrs. Knight drops her briefcase and it lands on the floor, the reaction force to the action force of the briefcase on the floor is the force of the floor on the briefcase (c). According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. Therefore, when the briefcase exerts a force on the floor (the action), the floor exerts an equal and opposite force on the briefcase (the reaction). This is the force that you feel when you catch something heavy or push against a wall. It's not to be confused with the force of gravity, the force of air, or the force of friction, which are all different types of forces that can act on the briefcase.