How Is the Spring Constant Calculated from Block Compression and Friction?

[soul5]

Homework Statement

A 1.8kg block slides on a rough, horizontal surface. The block hits a spring with a speed of 2.0m/s and compresses it a distance of 0.11m before coming to rest. The coefficient of friction between the block and the surface is 0.560. What is the force constant of the spring?

Homework Equations

Ep=1/2kx^2
Ek=1/2mv^2

The Attempt at a Solution

I used Ek=1/2mv^2 to find Ek and I got 3.6J. I can use Ff=uFn to find force friction, but I don't know what to do? help.

 

[MaZnFLiP]

Since you know the mass of the object you would also know the Force of Gravity. Since force of gravity = Normal Force whenever its perfectly horizontal, then you could use that number you got times mew to get your frictional force