Average and Instantaneous Velocity
Average or Instantaneous? Instantaneous velocity : the velocity of a moving object at one specific moment. Average velocity: velocity measured over a certain time interval. When might average velocity be LESS important than instantaneous velocity? Issuing speeding tickets When might average velocity be MORE important than instantaneous velocity? Calculating the length of a trip
Calculating average velocity from a position-time graph: Each section of the graph has a different slope representing individual velocities at that stage of the journey. The average velocity of the total graph or trip is found by using the beginning and end points.
Calculating instantaneous velocity from a position-time graph Draw a tangent line intersecting (but not crossing) the point (“time”) for which you wish to determine instantaneous velocity. Pick two points on this tangent line and calculate the slope.