2.  One for which work done does not depend on the path taken only on initial and final positions  Gravity and elastic forces are conservative  Why is kinetic energy not conservative?

3.  Total work is the same before and after a change  KE 1 + PE 1 = KE 2 + PE 2

4.  If only conservative forces act, the total mechanical energy in a system neither increases nor decreases

6.  If a stone is dropped from a height of 3.0m, what is the stone’s speed when it has fallen to 1.0m?

8.  A roller coaster car starts at the top of a 40m high hill a) find the speed of the car at the bottom of the hill b) at what height will it have half of this speed?

9.  What is the kinetic energy and speed required for a 70kg pole vaulter to just pass over a 5.0m high bar? The vaulter’s center of mass is.90m off the ground.

10.  Who will be going faster at the bottom?  Who will get to the bottom first?

11.  A dart gun of.100kg is pressed against the spring of a toy dart gun. The spring (k = 250 N/m) is compressed 6.0cm and released. What speed does the dart acquire?