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Homework Help: Help with velocity vs, time graph!

  1. Jan 19, 2010 #1
    1. The problem statement, all variables and given/known data
    Draw a velocity vs. Time graph Please I REALLY need HELP!?
    7. Sketch a velocity versus time graph of Tommy in his car for the following situation. [5]

    • He is waiting at a traffic light.
    • He accelerates up to the speed limit.
    • Travels at the speed limit for a while.
    • Decelerates when he sees a red light.
    • Stops at the light for a while.


    2. Relevant equations
    There are no equations


    3. The attempt at a solution

    I don't know how to draw this!
    I need help
    please!
     
  2. jcsd
  3. Jan 19, 2010 #2
    Okay, so if he is waiting at a traffic light, his velocity should=0. Time is still passing, so its a straight line but it sits on top of the x-axis (y=0). When he accelerates, his velocity will raise over time, so that's a positive diagonal line. Now he is cruising at a constant velocity. That's a straight line at some positive value of y. When he decelerates, the line goes downwards (make a negative slope) and it will eventually hit zero, where it will just go along the x-axis again.
     
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