Movement--Some basic principles

A.  Some units of measure
	1.  System international (SI)
		a.  meter
		b.  kilogram
		c.  liter
		d.  second
	2.  Prefixes
		a.  giga
		b.  mega
		c.  
		d.  milli
		e.  micro
		f.  nano
B.  Some general concepts
	1.  Object in motion will stay in motion, object at rest will stay
		at rest (unless other forces are applied or unless affected
		by frictional forces)
	2.  Conservation of energy and momentum
	3.  For every force an equal and opposite reactant forces
C.  Some definitions
	1.  Mass-amount of matter in an object.  kilograms
	2.  Velocity-distance per time unit.  meters/second
	3.  Acceleration-change in velocity.  meters/second second
	4.  Force--mass times acceleration.  newtons
	5.  Density--mass per unit of volume.  kilograms/m2
	6.  Work--Force * distance.  joules
	7.  Power--Work/time.  watts
	8.  Reynold's number --  (velocity * dimension)/viscosity
D.  Some thoughts about relationships
	1.  Anemone sitting on the bottom of the ocean produces is subjected
		to downward force (gravity).  At the same time the ocean floor
		produces equal but opposite force for the anemone.
	2.  Animal floating in the water column sinks because its specific
		gravity is greater than that of the medium it lives in
		To prevent sinking, organism can reduces its density (by
		retaining light ions, secreting gas, etc.) or increase
		its surface area to take advantage of the viscosity of the
		medium it is living in.  
	3.  Animals with high Reynold's numbers need to be streamlined in
		order to reduce energy expenditures.  Animals with low R's
		can take advantage of viscosity and don't need to be stream-
		lined.