A 75.3-kg boy is surfing and catches a wave which gives him an initial speed of 1.60 m/s. He then drops through a height of 1.65 m, and ends with a speed of 8.51 m/s. How much nonconservative work (in kJ) was done on the boy? X Can you express the nonconservative work done on the boy in terms of his change in kinetic and gravitational potential energy? Can you write expressions for the change in kinetic and potential energy? kJ