An object with a mass of #4 kg# is lying still on a surface and is compressing a horizontal spring by #1/4 m#. If the spring's constant is #3 (kg)/s^2#, what is the minimum value of the surface's coefficient of static friction?

1 Answer
Jun 3, 2017

The coefficient of static friction is #=0.02#

Explanation:

The coefficient of static friction is

#mu_s=F_r/N#

#F_r=k*x#

The spring constant is #k=3kgs^-2#

The compression is #x=1/4m#

Therefore,

#F_r=3*1/4=3/4N#

The normal force is

#N=mg=4gN#

The coefficient of static friction is

#F_r=(3/4)/(4g)=0.02#