An object with a mass of # 14 kg# is lying still on a surface and is compressing a horizontal spring by #1 m#. If the spring's constant is # 7 (kg)/s^2#, what is the minimum value of the surface's coefficient of static friction?
The surface's coefficient of static friction, in this case, will be 0.0051, approximately.
Since the object is lying still on the surface, it is in equilibrium and, therefore, the net force in it must equal zero:
Since it is placed by a horizontal spring, the friction force,
Now, since the displacement
Now, from Equation (1),
Since in this case the normal force equals the object's weight, then: