A child jumps from a moving sled with a speed of 2.5 m/s and in the direction opposite the sled’s motion. The sled continues to move in the forward direction, but with a new speed of 6.3 m/s. If the child has a mass of 38 kg and the sled has a mass 63 kg, what is the initial velocity of the sled?

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)