1. If a 6,000 kg Orca is able to accelerate from 0 to 45 km/h in 20.0 s, how much force is it using?

2. A 0.145 kg baseball is hit with a bat at an angle of 68 from the horizontal with a magnitude of 22.0 kN.What are the vertical and horizontal components of its acceleration?

3. Two people are pushing on an upright barrel with a mass of 24.0 kg on a frictionless surface.One pushes with a force of 27.0 N in a direction of 33 while the other pushes with 18.0 N at an angle of -41. How far does the barrel move in 12.0 s if it starts from rest?

4. There is a compressed spring between two blocks on a frictionless surface. When the spring is released the first block with a mass of 3.45 kg accelerates at a rate of 2.55 m/s². If the second block accelerates at a rate of 4.78 m/s², what is its mass?

Write down the key words or phrases for the following problems. Besides Newton's Second Law, what other equation is needed to solve the problem? Do not fully solve the problem. Do not solve the equation for the missing variable.

5. A person in a kayak starts paddling, and it accelerates from 0 to 0.60 m/s in a distance of 0.41 m. If the combined mass of the person and the kayak is 73 kg, what is the magnitude of the net force acting on the kayak?

6. A billiard ball strikes and rebounds from the cushion of a pool table perpendicularly. The mass of the ball is 0.38 kg. The ball approaches the cushion with a velocity of +2.1 m/s and rebounds with a velocity of 2.0 m/s. The ball remains in contact with the cushion for a time of 3.3 103 s. What is the average net force (magnitude and direction) exerted on the ball by the cushion?