1. The problem statement, all variables and given/known data In many neighborhoods, you might see parents pulling youngsters in a four-wheeled wagon. The child and the wagon have a combined mass of 50kg and the adult does 2.2 x 10^3 J of work pulling the two 60m at a constant speed. The coefficient of friction for the surfaces in contact is 0.26 1) Determine the magnitude of the force applied by the parent 2) Determine the angle at which the parent is applying this force. 3. The attempt at a solution 1) Given: m = 50kg W = 2.2 x 10^3 J d = 60m mu(kinetic) = 0.26 W = Fa cos(angle) d Fa = W / cos (angle) d Do I need to find the angle to solve this? 2) Constant speed so no acceleration, force applied = kinetic friction Fk = (Fn)(mu kinetic) (Fn)(mu kinetic) = W / cos(angle)d No vertical movement so Fn = weight = ma cos(angle) = W / (m)(a)(mu kinetic)(d) cos(angle) = (2.2 x 10^3 N/m) / (50kg)(9.8N/kg)(0.26)(60m) (angle) = 73 degrees Go back to 1): Fa = W / cos (angle) d Fa = (2.2 x 10^3 N/m) / cos(73)(60m) Fa = 125.41N Is this correct? Or does that value of work already have the angle included in its calculation..?