Answer
$0.21$
Work Step by Step
We can find the coefficient of static friction as follows:
$\Sigma F_x=\mu_s mg=\frac{mv^2}{r}$
This simplifies to:
$\mu_s=\frac{v^2}{rg}$
We plug in the known values to obtain:
$\mu_s=\frac{(2.2)^2}{(2.3)(9.81)}$
$\mu_s=0.21$
