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  1. what does hydrostatic weighting find? 

    what is the relationship between body fat and body density?
    uses density measurements to determine body fat

    there is high statistical correlation with an inverse relationship
  2. relative velocity
    • is the velocity of a body with respect to the velocity of something else
    • (comparing 2 different velocities of objects)
  3. relative velocity equation
    VO/F = VO – VF
  4. what is drag
    a resistance force which slows the motion of an object moving through a fluid
  5. fluid definition 

    ex. air or water
    a substance that flows and/or continuously deformed when acted upon by a shear force
  6. viscosity definition 

    what is it directly proportional to?
    resistance to deformation

    density and specific weight
  7. bouyancy
    the fluid force that acts directly upward
  8. archimedes principle definiton
    the buoyant force equals the displaced volume of the body
  9. center of volume
    the point where the objects volume is equally distributed and buoyancy acts
  10. what determines floatation? what primarily determines floatation?
    • -buoyancy and weight
    • -density (high density-sink, low density-float)

    increased buoyancy, decreased weight=float

    decreased buoyancy, increased weight=sink
  11. what is skin friction? how does it affect velocity and what kind of flow does it create?
    a type of drag that decreases velocity by creating a boundary layer (laminar and turbulent)
  12. pressure drag 

    factors influcencing
    pressure differential between the front and back of the body 

    • -relative velocity between object and fluid
    • -magnitude of pressure gradient 
    • -size of surface area thats perpendicular to flow
  13. Bernoulli's Principle
    regions of high velocity are associated with low pressure 

    regions of low velocity are associated with high pressure
  14. magnus effect
    a change in the trajectory of the spinning object towards the direction of the spin

    -low velocity with high pressure (the relative velocities going towards each other) will create lift.

    if they go in the same direction, the object lowers
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biomechanics last section