1. A ball of mass 1.2 kg is thrown from the top of a tower 52 m above the ground at an initial speed of 26m/sand at an initial angle of 31 above the horizontal. Air resistance does work of 217 J on the ball as it falls. Determine the impact speed of the ball.

2. A ball of mass 0.7 kg slides on a frictionless surface at a speed of 12 m/s (East) and collides with an initially stationary ball of mass 0.9 kg. After the collision, the lighter ball is deflected by an angle of 39 North of East, and the heavier ball is deflected by an angle of 25 South of East. Determine the speeds of the two balls after the collision.

3. A person pushes on a door with a force of magnitude 51 N. The force is applied horizontally at a distance of 47 m from the hinges, and at an angle of 62 measured relative to the line joining the hinges to the position where the force is applied. Determine the magnitude of the torque of the force relative to the line through the hinges.

4. Two carts collide on a frictionless surface. Before the collision, one cart (mass 7.2 kg) is at rest and the second cart (mass 12.5 kg) has a speed of 15 mfs. After the collision, the two carts stick together. Determine the speed of the composite body after the collision.