1. The problem statement, all variables and given/known data The spring in the figure has a spring constant of 1100 N/m. It is compressed 14.0 cm, then launches a 200 g block. The horizontal surface is frictionless, but the block's coefficient of kinetic friction on the incline is 0.210. What distance d does the block sail through the air? 2. Relevant equations Work of spring: W(spring) = 1/2*k*s^2 Work of Friction + Gravity as block slides up incline: W(friction) = -u*k*n*s = -u*k*Wx*s = -u*k*m*g*cos(theta) * s W(gravity) = Wy * s = m * g * s * sin(theta) Work-Energy Theorem W(net) = (delta)K = Kf - Ki Projectile Motion Kinematics: Vfy = Viy - g * t Xf = Xi + Vix * t 3. The attempt at a solution Using the work equations above, I found the net work at the top of the ramp to be 10.47J (10.7J from spring initially - 0.041J of friction - 0.19J of gravity = 10.47J), and then I used the Work-Energy equation to find the final velocity at the top of the ramp to be 10.23 m/s. Using this velocity and the fact that the launch angle is 45 degrees, I found the x and y components of the launch velocity and plugged them into the equations above to get the time the block spent in the air, and then finally the final distance traveled by the block, which I found to be 5.41m. Unfortunately, this answer is incorrect. After looking around the web for a while for another reasonable solution I found that most answers given were about double mine, as in 10.48m instead of 5.41m. After trying this answer, I found it was also wrong. Any help would be appreciated.