A 15-pound box sits at rest on a horizontal surface, and there is friction between the box and the surface. One side of the surface is raised slowly to create a ramp. The friction force f opposes the direction of motion and is proportional to the normal force F exerted by the surface on the box. The proportionality constant is called the coeficient of friction, u. When the angle of the ramp. 0, reaches 25°, the box begins to slide. Find the value of u The value of u is O (Do not round until the final answer. Then round to two decimal places as needed)

A 15-pound box sits at rest on a horizontal surface, and there is friction between the box and the surface. One side of the surface is raised slowly to create a ramp. The friction force f opposes the direction of motion and is proportional to the normal force F exerted by the surface on the box. The proportionality constant is called the coeficient of friction, u. When the angle of the ramp. 0, reaches 25°, the box begins to slide. Find the value of u The value of u is O (Do not round until the final answer. Then round to two decimal places as needed)