Card Set Information

2013-09-26 15:56:35

Show Answers:

  1. fundamental unit
    basic units from which all other units are made
  2. derived unit
    units that are a combination of two or more of the fundamental units
  3. converesions
    1 hr = 3,600 s

    1km = 1,000 m
  4. to change an object's motion you need __ __.
    the change an object's motion you need unbalanced forces.
  5. constant or no motion means __ __.
    constant or no movement means balanced forces.
  6. three ways to describe motion
    • words
    • math
    • graphs
  7. reference point
    "zero" location in a frame of reference
  8. frame of reference
    a number line used to describe motion
  9. position
    separation between the object and reference point
  10. scalar quantity
    • quantity that only has size/magnitude
    • # and unit
    • distance is scalar
  11. vector quantity
    • quantity that has size, magnitude and direction
    • #, unit and direction
    • acceleration, position, displacement, velocity
  12. instantaneous position
    position at a certain time
  13. distance (d)
    • measures the separation between two objects
    • needs no reference point
    • scalar quantity
  14. displacement (Δd)
    • change in position of an object (start point to end point)
    • vector quantity
  15. average velocity (v wit line)
    the displacement of an object divided by the time interval over which it moved.
  16. If the average velocity is the same throughout the time interval then we have __ __.
    If the average velocity is the same throughout the time interval then we have constant velocity.
  17. Speed vs. Velocity
    speed: distance divided by time; scalar quantity

    velocity: displacement divided by time; vecotr quantity
  18. acceleration
    the rate of change of velocity; change of velocity divided by time.

  19. velocity-time graphs
    • the slope of a velocity-time graph represents acceleration.
    • the area under a velocity-time graph represents displacement (vector quantity).
  20. distance-time graphs
    the slope of a position-time graph represents velocity (speed).

  21. linear motion
    motion that occurs in  straight line
  22. equation for constant acceleration
  23. equation for when acceleration is constant and we do not have final velocity
  24. equation used when acceleration is constant and you do not have time
  25. summary of three equations
    no displacement :  

    no final velocity : 

    • no time :