1. The masses shown below are initially at rest. a) Find the final speed v of the 4 kg mass after the masses are pushed apart in an explosion. (6.57 m/s) b) Find the initial and final KE of the system (0 J; 240.3 J) c) The final kinetic energy is greater than initial kinetic energy. Does this violate the law of conservation of energy? Explain 4 m/s 6 m/s 20 30 5 . before after 2. A 8 kg mass slides from a height of 16 m down a frictionless ramp. It then collides and sticks to a stationary 2.5 kg mass, and together the masses complete a 3 metre radius loop. a) discuss the principles of physics that apply to this situation b) Find the normal force on the masses at the top of the loop. (122.6 N) 8 kg 16:m 2.5 kg r =3 m 3. Find the forces exerted by the two supports on the beam shown below. Note the beam mass and length given on the diagram. (402 N down; 772 N up) 120 N 80 kd rope .11 1 0.5 m 5 m 1.25 m beam is 6 m long has mass 50 kg support 1 support 2