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B The impulse of an object during deployment

  1. Oct 28, 2018 #1
    how do I find the impulse of an object when it is deployed. (here is an image of the deployment method, It is just a string)
    Thanks so much!!!!!
    delta
     

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  3. Oct 28, 2018 #2

    russ_watters

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    I'm having trouble understanding what is happening in that picture -- can you describe it or provide a diagram? From the picture it looks like a high school lab...?
     
  4. Oct 28, 2018 #3
    thanks so much for responding! okay so the picture is of the release mechanism, which is just a string attached to a bottom of the basket. the string is held so that the basket can be released without the person touching the basket. also the basket is being released down a zipline.
    delta
     
  5. Oct 28, 2018 #4

    russ_watters

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    You're welcome!

    So are you asking about the impulse provided by the release mechanism or by the whole trip on the zipline?
     
  6. Oct 28, 2018 #5
    Im asking about only the impulse provided by the release mechanism
    thanks!
    delta
     
  7. Oct 28, 2018 #6

    russ_watters

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    The string is just holding the car still and then you just let go of the string? I suppose if you don't hold the car back and it doesn't swing when released, and the car is a lot heavier than the string, there is little or no impulse provided by letting it go.
     
  8. Oct 28, 2018 #7
    thank you so much!!! this is super helpful!
    delta
     
  9. Oct 29, 2018 #8

    sophiecentaur

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    The problem with trying to find the "Impulse" is that it requires knowledge of the time taken
    Impulse = Force X time
    If you want to find the speed (and then the Momentum, if you want it) it is often better to consider the Energy involved.
    The Energy supplied is Force X Distance and that would turn up as Kinetic Energy. In your case, the Force can vary over the period so you could do some integration - or even measurement of force over the range but time is not an issue so that method has advantages. Actually, the Kinetic Energy gained by the 'car' will just be due to the change in height, whatever arrangement you use. That's true unless there is some extra energy stored in spring or rubber band - which I cannot see.
    I always go for Energy, rather than Momentum when possible if I have a problem to solve.
    PS Do you have a method for actually measuring the final speed of the car?
     
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