A book with mass 4.0 kg is initially at rest on a smooth horizontal surface. A student then applies a horizontal force to it. As a result, the book moves along the x-axis such that its position is given by x(t) = 0.2t2 0.02t3 where x is in meters and t in seconds. (a) Find the velocity of the object when t = 4.0 s. (b) What is the magnitude of the force when t = 4.0 s? (c) Calculate the work one by the force during the first 4.0 s of the motion.
