Question

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

Answer 1

The coefficient of static friction is `=0.1`

Explanation:

The force of friction is

`F_r=k*Deltax`

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

The compression of the spring is `Deltax=1/3m`

Therefore,

`F_r=3*1/3=1N`

The coefficient of static friction is

`mu_s=F_r/N`

The normal force is `N=mg=(1g) N`

The acceleration due to gravity is `g=9.8ms^-2`

So,

The coefficient of static friction is

`mu_s=(1)/(1g)=0.1`