The next two questions are worth 20 points in total. For both questions, consider the following: A 12 kg cart is connected by a light string over a pulley to a hanging 4 kg mass. The coefficient of friction between the cart and the horizontal track is μk = 0.20. The pulley does not spin as the string passes over it. If the cart and mass are released from rest, you want to find the speed of the two objects immediately before the hanging mass hits the floor.
1. What is the total kinetic energy of the cart-mass system?
A. 62.7 J
B. 39.2 J
C, 100 J
D. 25.1 J
E. 79.3 J
2. What is the speed of the cart and mass?
A. 2.50 m/s
B. 3.54 m/s
C. 2.04 m/s
D. 5.60 m/s
E. 1.77 m/s