A 1.00 kg mass slides to the right on a surface having a coefficient of kinetic friction 0.250. The object has a speed of vi = 3.00 m/s when it makes contact with a light spring that has a force constant of 50.0 N/m. The object comes to rest after the spring has been compressed a distance d. The object is then forced toward the left by the spring and continues to move in that direction beyond the spring's unstretched position. Finally, the object comes to rest a distance D to the left of the unstretched spring.

Question

myname · Answer

(a) Find the distance of compression d.

myname · Answer

http://www.webassign.net/pse/p8-62.gif

myname · Answer

This is what i have

Total Work = Kf - Ki

Then i used ------> Total Work =  -((1/2)*k*(x^2) + N*(0.250)*x)

myname · Answer

This is what should be i guess but, i am getting a wrong answer which is ten percent off.