1) a 500 kg car is travelling at 15 m/s and experiences a forward engine force of 2000N for 3 seconds. The combined frictional forces acting on the car are 600 N. What is the car's acceleration?
2) Four people are pushing on a box where the box has no friction but their feet do. Person #1 pushes with 22N to the right, person #2 with 14 N to the right, and and person #3 pushes with 30 N to the right. Person #4 pushes with 72 N to the left. The box has a mass of 5 kg; determine acceleration.
3) Edward applied a horizontal force to stop a pickup truck that was sliding toward Bella. Find the magnitude of the horizontal force needed, if the truck, going from an initial speed of 14 m/s, stopped over a distance of 1.0 m (the length of Edward's arms). The truck's mass is 1600 kg.