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Velocity versus Time Graph help?

  1. Sep 13, 2014 #1
    What does a vertical line graph pointing straight up mean? Same for down? What does a horizontal line mean?

    y axis=velocity (m/s)

    x axis=time (s)
    Last edited: Sep 13, 2014
  2. jcsd
  3. Sep 13, 2014 #2


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    Vertical line doesn't mean anything. It's not even a proper function. f(x) can have only one output per x.
    It doesn't make sense intuitively either: one body cannot have simultaneously every possible velocity.

    Horizontal means constancy.
  4. Sep 13, 2014 #3
    I was doing a lab with my group where we had to use a motion detector to match the target graphs given. And yes, my axes are correct. (University Physics 1)
  5. Sep 13, 2014 #4

  6. Sep 13, 2014 #5


    Staff: Mentor

    Bandersnatch is correct. A vertical line on a velocity time graph is nonsense. It means that the object has every velocity and only exists for an instant.

    A horizontal line means a constant speed.
  7. Sep 13, 2014 #6


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    It could help to add that a 'nearly vertical' line would represent a very rapid change of velocity - thus avoiding the problem of every velocity existing at once. 'Near as dammit', instant change of velocity - as when a ball bearing hits the front of a locomotive. The line is not quite vertical.
  8. Sep 13, 2014 #7


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    Right- the ball bearing has just enough time to say "ouch"!
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