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**Kinematics problems:**

1. A boat starting from rest on a lake accelerates in a straight line at a constant rate of 2.0 m/s^2 for 6.0 s. How far does the boat travel during this time?

2. A bullet traveling horizontally at a speed of 350 m/s hits a board perpendicular to the surface, passes through it, and emerges on the other side at a speed of 210 m/s. If the board is 4.00 cm thick, how long does the bullet take to pass through it?

**Work and Energy problem: (equations: W=Fdcos(theta), Wnet = change in K, U= mgh, K=1/2mv^2, E = K + U, Fnet=ma, Fg = mg)**

1. A 500 kg helicopter ascends from the ground with an acceleration of 2.00 m/s^2. Over a 5.00-s interval, what is the work done by the lifting force?

2. An automobile with a mass of 1200 kg travels at a speed of 90 km/h. What force would be required if it took 100 m to stop?

3. A person standing on a bridge at a height of 80 m above a river drops a 0.250-kg rock. (a) What are the rock's kinetic and potential energy at the time of release relative to the surface of the river? (b) What are the energies just before the rock hits the water?