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Position Time Graph Help

  1. Jul 10, 2015 #1
    Can the position-time graph tell you the speed?
    I thought it was ONLY velocity.

    Can you please give me an example when IT DOESN'T allow you to find the speed?

    Thanks so much in advance!!
  2. jcsd
  3. Jul 10, 2015 #2


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    Speed is the magnitude of the velocity, if you can find the velocity you can always obtain the speed.
  4. Jul 10, 2015 #3


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    Presumably we are talking about motion in one dimension, otherwise it's not clear what the position axis represents.

    In which case a graph of position vs time gives you speed and velocity. The direction component of velocity comes from the slope of the line. +ve slope is away from the origin, -ve slope is towards the origin.
  5. Jul 10, 2015 #4
    Just to piggyback for additional clarity: if you find the slope of the tangent line on a position vs. time graph you have found the velocity at that instant. The absolute value of the slope is the speed.
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