Question

A 25 N force at 60° is required to set a crate into motion on a floor. What is the value of the static friction?

Answer 1

The normal force of the force given is calculated through the equation,
 
                                 Fn = F(sin θ)
where Fn is the normal force, F is the force, and θ is the angle. 
  
                                Fn = (25 N)(sin 60°) = 21.65 N

The x-component of the force applied is,
                               Fx = (25 N)(cos 60°) = 12.5 N

The value of the coefficient of static friction is calculated through the equation,
                              F = μFn
                              μ = Fx / Fn = 12.5 N / 21.65 N = 0.577