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Homework Help: Archived Did I make the velocity vs time graph correctly?

  1. Oct 16, 2012 #1
    1. The problem statement, all variables and given/known data
    a) Calculate the slope for each segment
    b) Describe the motion the object experiences in each segment
    c) Make a velocity vs time graph using the slopes
    d) Make a acceleration time graph

    (for the distance-time graph)
    Segment A slope of zero
    Segment B constant slope of +1
    Segment C slope of zero
    Segment D sharp change to slope of -3
    Segment E sudden change to slope of zero
    Segment F constant slope of -2/5
    Segment G slope of zero

    2. Relevant equations

    slope = deltaY/deltaX
    acceleration = deltaV/deltaT

    3. The attempt at a solution

    I'm fine on a and b, but for c my graph just has horizontal segments at varying y values that correspond to the earlier velocities (slopes). I think this may be wrong. Anyway if it isn't does that mean that my acceleration-time graph will be a load of horizontal lines since all the velocity changes were sudden and constant?
  2. jcsd
  3. Feb 25, 2016 #2


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    Last edited: Feb 25, 2016
  4. Feb 25, 2016 #3


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    That is correct. The Velocity in each section is the slope of the distance/time graph in that section.

    No. The acceleration at any instant is equal to the slope of the velocity/time graph at that instant. Sudden or rapid change in velocity mean large acceleration. The Velocity graph has instantaneous changes in velocity followed by periods of constant velocity. This means infinite acceleration for very short periods of time followed by periods of zero acceleration.
    Last edited: Feb 25, 2016
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