Question

At the top of an inclined track, a spring is attached to a rod at one end and a dynamics cart at the other such that the spring stretches parallel to the track. The cart has a mass of .850kg and there is negligible friction between the cart and the track. The spring has a force constant of 12.5 N/m. Determine the stretch length of the string if the track makes an angle of 12 degrees above the horizontal.