A toy cannon uses a spring to project a 5.30 g soft rubber ball. The spring is originally compressed by 5.00 cm and has a force constant of 9.00 N/m. When it is fired, the ball moves 16.0 cm through the horizontal barrel of the cannon, and a constant frictional force of 0.0320 N exists between barrel and ball. (a) With what speed does the projectile leave the barrel of the cannon? Wnet = [tex]\Delta[/tex]KE Ws - Wfk = .5mv2 - 0 .5kx2 - fkd = .5mv2 .5(9)(.052) - (.032)(.11) = .5(.0053)v2 v = 1.7079 Final answer is incorrect. Any ideas?