Question

1. the force needed to start a box moving from rest on a horizontal surface is _. options: equal to the normal force, equal to the force from gravity, less than the maximum force from static friction, greater than the maximum force from static friction

Explanation:

Step1: Recall friction - force concept

The force needed to start an object moving from rest on a horizontal surface is the force required to overcome static - friction. The maximum static - friction force is given by $F_{s,max}=\mu_sN$, where $\mu_s$ is the coefficient of static friction and $N$ is the normal force. To start the box moving, the applied force must be greater than the maximum static - friction force acting on the box.

Answer:

Greater than the maximum force from static friction