5. (20 pts) One dimensional motion diagram: The dots show the positions of a cart every two seconds as the cart moves along a N straight low friction track. The cart, originally moving south has a fan which causes the cart to slow down, change directions, and then speed up in the opposite direction. North is chosen as +x. The motion of the cart while moving south is shown on the left of the ruler and the northward motion on the 120 cm (10) right. The t = 4s position when the cart changes directions is shown on both sides of the ruler. a. Draw motion diagram showing vectors representing the velocities and acceleration vectors for this motion. You may need to offset the vectors so that they don't overlap each other. Write ~ 0 (with 80 cm label) if a quantity is zero. b. Determine the average x-velocity between 8 sec and 10 sec. This allows us to estimate the x-velocity at t = 9 s. We won't be stating this explicitly from now on, but ALWAYS follow 40 cm the rules for showing your work and labeling your answer, i.e., start by writing down the relation you will use symbolically, show the numbers you use, and label the answer at the end. Include units. ocm C. What is true of the x-acceleration during this motion? Does it change? Is it constant? Does it change directions? What -40 cm 8 direction does it point? 0) -80 cm d. What is the x-acceleration? -120 cm 2 ) -160 cm (4) (4)