practice problems for energy - to do for Wednesday's class

These will NOT be collected, but an assignment given Wednesday afternoon WILL be collected during class on Friday.

1.  Define energy.

2.  Define PE and KE .

3.  What is the conservation of energy principle?

4.   Consider a 5-kg bowling ball that has been raised to 2-m above the ground.  Find the following:

a.  initial PE
b.  final KE right before it hits the ground
c.  PE and KE right in the middle of the drop (1-m above the ground)
d.  speed right before hitting the ground - treat this as an energy problem
e.  does the mass matter for part d?  Explain.

You may let g = 10 m/s/s for this problem, if you like.



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