Problem 1 (3.0 pts.). A soccer ball of a mass m = 1,000 g is traveling with kinetic energy is KE = 40.5 J. Find the speed and the momentum of the ball. Problem 2 (3.5 pts.). (a) What is the gravitational force acting between two watermelons of masses m = 5,600.0 g and m2 = 7,200.0 g located 2.5 m away from each other? (b) Find the distance between the place where the two watermelons are located and the Sun if the gravitational force acing on the first watermelon with mass m = 5,600.0 g and the sun is F = 0.029 N. The mass of the Sun is M = 1.99 100 kg. Problem 3 (3.5 pts.). A box of a mass M = 20 kg initially at rest is pushed by a force F = 360 N, as is shown in Fig. 1. There is also an unknown friction force acting on the box. (a) Find the the friction force f if acceleration a of the box is a = 0.2m/s2. What will its final speed be after t = 10 sec. of such motion? Can we say that the total mechanical energy in this process is conserved? (b) Find the distance traveled by the box, and the work done by the force F. F M Figure 1: Schematic graph for Problem 3.