An object with a mass of # 2 kg# is lying still on a surface and is compressing a horizontal spring by #70 c m#. If the spring's constant is # 9 (kg)/s^2#, what is the minimum value of the surface's coefficient of static friction?

1 Answer
Apr 25, 2017

The coefficient of ctatic friction is #=0.32#

Explanation:

The force of friction is

#F_r=k*Deltax#

The spring constant is #k=9kgs^-2#

The distance is #Deltax=0.7m#

Therefore,

#F_r=9*0.7=6.3N#

The coefficient of static friction is

#mu_s=F_r/N#

The normal force is #N=mg=(2g) N#

So,

#mu_s=(6.3)/(2g)=0.32#