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Momentum/Impulse Graph Finding Velocity

  1. Nov 5, 2006 #1
    Momentum/Impulse Graph....Finding Velocity

    A 0.125 kg ball, moving in the positive direction at 12 m/s, is acted on by the impulse shown in the graph in Figure 9-16 What is the ball's speed at 4.0 s?

    If the picture doesnt load as an attachment I'll have to try it again.

    Okay so I'm not sure where to start when lookin at this graph. I think I start with finding the original momentum which is 1.5. The main problem is reading the graph. Again with this one I'm just stuck with how to read the graph.


    Attached Files:

  2. jcsd
  3. Nov 5, 2006 #2
    Can someone point me in the right direction?
  4. Nov 5, 2006 #3


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    The graph does not load. Try again.

  5. Nov 5, 2006 #4
    It says they are pending approval.
  6. Nov 5, 2006 #5


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    Is it a velocity-time graph?
  7. Nov 5, 2006 #6
    Nope there is Force in the Y and Time in the X
  8. Nov 5, 2006 #7
    On the Y there are 3 tick marks in this order top to bottom 2 0 -2.
    On the X there are the numbers 1-4 (time in seconds).

    From 0-1 in the X it follows the 0 on the Y, from 2-3 there is an impulse that goes up to the 2 (Coordinate 2,2) in the Y then from 3-4 it remains on 0 force. Probably nm help but not sure what else to do like getting it approved or w/e.
  9. Nov 5, 2006 #8
    Does anyone know how to get the image approved?
  10. Nov 5, 2006 #9


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    So it looks like a square wave, right? 0, then 2, then 0? Do you know the impulse formula? If you do, you have all but 1 variable.
  11. Nov 5, 2006 #10
    triangle wave and the point is between 1-3 on top of the 2 in the X...ive tried that but it doesnt give me the answer.

    i can find initial momentum but how do i find speed at 4 seconds?
  12. Nov 5, 2006 #11
    Impulse is the change in momentum. Find the area under the curve and add that to the initial momentum
  13. Nov 5, 2006 #12
    that didnt do it
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