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Homework Help: How would you graph this?

  1. Oct 8, 2011 #1
    Please provide coordinates on the following graph (or a picture if possible) as displacement vs time, velocity vs time, acceleration vs time, or all of these, which would be greatly appreciated

    1) *P1 stays at rest for 7 minutes, *P2 stays at rest for 2 minutes

    2) P2 walks to their locker for 5 minutes at 12m/min South

    3) P2 walks North towards P1's locker, which is halfway between their locker and the starting point, at 45m/min

    4) P1 walks to their locker (from the starting point) at 75m/min

    5) Once P2 arrives at P1's locker, they both must walk to a local restaurant 750m South from the starting point. They try to get here in 6 minutes. P1 and P2 both take 2 minutes to reach their top speed. P1's top speed is 120m/min, and P2's top speed is 160m/min.

    *P1 = Person 1
    *P2 = Person 2

    Thanks, and this would really mean a lot

    My attempt:



    I have no idea how to do an acceleration vs time graph of this by the way
    Last edited: Oct 9, 2011
  2. jcsd
  3. Oct 8, 2011 #2


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    We cannot do your homework for you. You must show your attempts so that we can advise. This is as per PF rules, which you (and any responders) read and agreed to. Members attempting to provide answers without you showing your attempts can, have been and will be given infractions.
  4. Oct 8, 2011 #3


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    Okay I will try my best to explain it...When person one is not in motion and just standing still you represent it on a Position vs Time graph as a horizontal line, because he is not moving but time is elapsing. Like wise for velocity time graph because P1 is not in motion and is standing still you will draw the horizontal line on the orgin as time is elapsing but his velocity is 0. Also to keep in mind based on common coordinate system right is positive and left is negative. Hope that gives you some perspective. If that still doesn't help I will than try to explain using your examples. I want to see if you can understand it without actually showing you the answer.
  5. Oct 9, 2011 #4


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    Try downloading a program called sigma plot...it will help you graph it or use excel
  6. Oct 9, 2011 #5
    I dont think I will be able to use a program like that, I'm only in high school, but I'll try

    But could you run me through the steps so I can get this right because this is worth a lot of marks, and if I get one step wrong, the rest of the graph will be marked wrong

    Last edited: Oct 9, 2011
  7. Oct 9, 2011 #6


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    Can you tell me what each line is doing? if so, this will help you greatly. Here in Physics forums we can't really do the homework for you but I will try my best to help you get it right :)
  8. Oct 9, 2011 #7
    A is going back to the source
    B is going away from the source
    C is staying at rest with an offset
    D is slowing going a way from the source
    -All velocities are constant

    What I'm most confused about is how to do #5 so if you could show me how to do that part, that would be great

    For points 7.66666666,270 (P1) and 7.666666666,390 (P2), I put a curve for acceleration but I don't know if this is right because the next part of each line just continues as if I never put a curve there (it is completely straight). What should I do?
    Last edited: Oct 9, 2011
  9. Oct 9, 2011 #8


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    Well they both accelerate at first so it would curve up to 2 minutes, after that for another 4 minutes its a straight line as they continue to walk at there top speed.
  10. Oct 9, 2011 #9
    I know that, I don't think you're reading my whole post or maybe you're just ignoring most of it
  11. Oct 10, 2011 #10


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    Well I answered your question regarding #5. Of course I will not tell you the exact answer to the question as that is no help to you. I might be misunderstanding what your really trying to ask. I apologize if I caused any confusion.
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