So with this in mind, I'm guessing I will have to re-calculate the velocity of the box, the acceleration and coefficient value.
m1v1+m2v2=(m1+m2)v1'
(0.125)(0.71)+(0.2673)(0) = (0.125+0.2673)(v1'), v1' = 0.23m/s
(vf^2-vi^2)/2d = a
(0^2 - 0.23^2) / 2(0.032) = a, a =-0.83 m/s
-0.83/9.8 = μ
μ =...