# A child starts sledding from rest, going down a 40 m long 7.5° incline, then coasting across a horizontal stretch. The mass of the sled

A child starts sledding from rest, going down a 40 m long 7.5° incline, then coasting across a horizontal stretch. The mass of the sled + child is 35 kg, and the coefficient of kinetic friction is 0.060. a)Make force diagrams for the sled + child on both the hill and the horizontal stretch. b)Resolve the weight of the sled + child along and perpendicular to the plane. c)Determine the reaction force on the sled + child. d)Determine the speed of the sled + child at the bottom of the incline. e)How far along the horizontal stretch does the sled + child travel before stopping? f)What is the total time for the ride? g)Determine how much energy that is transferred to thermal energy. h)Determine how much work is done on the sled + child by the gravitational force while the child + sled is moving along the incline. i)By considering the energy of the system and energy transformations, determine the speed of the sled + child at the bottom of the incline. Does your answer agree with part d?