An object with a mass of # 9 kg# is lying still on a surface and is compressing a horizontal spring by #2/3 m#. If the spring's constant is # 4 (kg)/s^2#, what is the minimum value of the surface's coefficient of static friction?

1 Answer
May 20, 2017

Answer:

The coefficient of static friction is #=0.03#

Explanation:

The coefficient of static friction is

#mu_s=F_r/N#

#F_r=k*x#

The spring constant is #k=4kgs^-2#

The compression is #x=2/3m#

Therefore,

#F_r=4*2/3=8/3N#

The normal force is

#N=mg=9gN#

The coefficient of static friction is

#F_r=(8/3)/(9g)=0.03#