1. The problem statement, all variables and given/known data The 3.8-kg collar is released from rest at A and slides down the inclined fixed rod in the vertical plane. The coefficient of kinetic friction is 0.51. Calculate (a) the velocity v of the collar as it strikes the spring and (b) the maximum deflection x of the spring. I have attached an image of the question. 2. Relevant equations 3. The attempt at a solution I was able to find the velocity of the collar with: U1 + K1 = U2 + K2 + F K1 and U2 are 0 F is the friction force 0.5mv2 = mgh1 - F Drawing a FBD of the collar shows that the Normal force (F = ukN): N = mgsin(27) 0.5(3.8kg)v2 = (3.8kg)(9.81 m/s2)(0.57sin(63)) - (0.51)(0.57m)(3.8kg)(9.81m/s2)sin(27) Solving for v gives me: v = 2.7157 I can't seem to find the displacement of the spring though. I realize that F = -kx and I need to find F to get x. Looking at the practice question (identical scenario but different numbers) led me to believe that the answer should be: F = mg - mgsin(27) x = sqrt[mg-ukmgsin(27)/2700] x = 103 mm But it says this isn't correct and I'm not sure where I'm making my mistake. Help is appreciated.