1. You are standing on a large sheet of frictionless ice and holding a large rock. In order to get off the ice, you throw the rock so it has velocity 12.0 m/s relative to the earth at an angle of 35.0 above the horizontal. Your mass is 72.0 kg and the rock's mass is 4.00 kg. a) What is your speed after you throw the rock? Express your answer with the appropriate units.

2. Two skaters collide and grab on to each other on frictionless ice. One of them, of mass 72.0 kg, is moving to the right at 4.00 m/s, while the other, of mass 67.0 kg, is moving to the left at 2.50 m/s. a) What is the magnitude of the velocity of these skaters just after they collide? Express your answer with the appropriate units. b) What is the direction of this velocity? to the left or to the right?

3. Two cars collide at an intersection. Car A, with a mass of 1900 kg, is going from west to east, while car B, of mass 1300 kg, is going from north to south at 13 m/s. As a result of this collision, the two cars become enmeshed and move as one afterwards. In your role as an expert witness, you inspect the scene and determine that, after the collision, the enmeshed cars moved at an angle of 60 south of east from the point of impact. a) How fast were the enmeshed cars moving just after the collision? Express your answer in meters per second. b) How fast was car A going just before the collision? Express your answer in meters per second.

4. A 0.149 kg glider is moving to the right on a frictionless, horizontal air track with a speed of 0.810 m/s. It has a head-on collision with a 0.310 kg glider that is moving to the left with a speed of 2.23 m/s. Suppose the collision is elastic. a) Find the magnitude of the final velocity of the 0.149kg glider. Express your answer in meters per second. b) Find the direction of the final velocity of the 0.149kg glider. to the right or to the left? c)Find the magnitude of the final velocity of the 0.310kg glider. Express your answer in meters per second. d) Find the direction of the final velocity of the 0.310kg glider. to the right or to the left?