10) Shawn (m = 49.0 Kg) rides his skateboard at a local skate park. He starts from rest at the top of the track as seen in the figure bellow ( view file in Course content ) and begins a descent down the track , always maintaining contact with a surface. The mass of the skateboard is negligible, as is friction except where noted . What is his speed when he reaches the bottom ( the end of the 180m lengh of track ) ? Dado m = 49.0 Kq FK = 115 N Total potential energy at maximum height = 12.0 m Kinetic energy at bottom Problema # 20 Fx 12.0 m 8.0 m 18.0 m FK = 115 N