Situational Analysis. Air are often pumped inside a tire in order to keep it rolling across the road. A driver accidentally pumped low amount of air in the truck’s tire. While travelling on the road he observed that the truck become unstable. He moved down and checked the source of the problem. He found out that the tire was almost deflated due to the minimal amount of air pumped. 1. How can air pumped in the tire hold up a truck?

3. On a very rainy day, Nick drags a box of old books to the bookstore to sell. The box moves through the puddles at U = 10 ft/min. For all calculations use an approximation that the box follows the figure. Calculate the force required to keep the box moving at U. Hints: obtain drag coefficient by calculating the Reynolds number; consider the projected area as the bottom plus the two long sides. • Determine the power (in watt) required to overcome the skin friction drag B = 2 ft L=3 ft -Water line D = 2 in