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Homework Help: Velocity and Acceleration (t,v) graph HELP please!

  1. Sep 17, 2012 #1
    As a car passes point A on a straight road, it's speed is 10m/s, the car moves with constant acceleration, a m/s/s, along the road for T seconds until it reaches point B, where it's speed is Vm/s.
    The car travels at this speed for a further 10 seconds, when it reaches the point C. From C it travels for a further T seconds with constant acceleration 3a m/s/s until it reaches a speed of 20 m/s at the point D.

    Sketch the [t,v] graph for the motion, and show that V=12.5

    I had no problem with showing V = 12.5 through a simultaneous equation.

    However part B states,
    The distance from A to D is 675m, find a and T

    Any help will be so very greatly appreciated!
    Thanks in advance
    Last edited: Sep 17, 2012
  2. jcsd
  3. Sep 17, 2012 #2
    The area under the graph of velocity is the distance traveled. The area, as should be obvious from the sketch, is a sum of three simple areas. Together with the equation you used for velocity, you should be able to determine a and T from it.
  4. Sep 17, 2012 #3
    If you can sketch the [t,v] graph for the motion, then you can deduce the answer.
    The area under the graph is the distance.
  5. Sep 18, 2012 #4
    Thanks a lot for the help!

    I got it now (:

    Thanks Again
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