Question

A large box sits on a rough floor. A person pushes on the box with a horizontal force of magnitude 50 N. The box remains at rest. What is the magnitude of the friction force

Answer 1

Answer:

The magnitude of the frictional force is   $F_f \ge 50 \ N$

Explanation:

From the question we are told that

   The force exerted on the box is  $F = 50 \ N$

Generally for the box to remain at rest then it means that the frictional  force is greater than or equal to the force applied to move it i.e

         $F_f \ge F$

=>      $F_f \ge 50 \ N$