Question

Assignments KHW02 1D Motion with Variable Acceleration 7 of 7 Consider a one-dimensional acceleration that starts at zero at time zero, then increases to some maximum value, then decreases back to zero. Human pushing forces often create accelerations that fit this description; the pushing force is small when the hands of the human first make contact (assuming the fingertips touch first), large when the palms are flat against the object being pushed, and then small again as the fingertips are breaking contact with the object This problem will ask you to find the resuiting velocity and position equations for a particle subject to such an acceleration. Assume that the object being accelerated is a cart that can roll without friction on a level floor. Also assume that the acceleration is always eastward, that the x axis has been chosen to be in the E-W direction with eastward positive, and that the r acceleration can be modeled by a quadratic equation a, (t)204.0 cm/st 156.0 cm/s4 )t2 This equation is valid between time zero (when the acceleration is zero) and some time tend, when the acceleration is again zero. Also assume that, at time zero, the velocity of the rolling cart is 14.53550 cm/s WEST and that the position of the cart at time zero is chosen to be the origin. Part A Make a sketch of the r acceleration as a function of time, and answer the following questions (questions A and B) about that acceleration. The acceleration is zero at time zero. What is the time tend when the acceleration is again zero? eol Submit Part B What is the maximum value of aoceleration and at what time does this maximum acceleration occur? For future referenoe, denote this time as taz Give your answer as an ordered pair, with the time when the maximum acceleration occurs being first, followed by a comma, then followed by the maximum value of the acceleration. View Available Hintfs) mar,amar s cmis

Answer 1