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Homework Help: Crossbow acceleration

  1. Aug 29, 2005 #1
    This is a two step problem:

    a) In deep space (no gravity), the bolt (arrow) of a crossbow accelerates at 193 m/s2 and attains a speed of 124 m/s when it leaves the bow. For how long is it accelerated?

    b) What speed will the bolt have attained 3.6s after leaving the crossbow? Answer in m/s

    I correctly figured out that it is accelerated for .642 s. But I don't quite understand what happens afterwards. Since there is no gravity, doesn't the acceleration continue? I multiplied 193 by 3.6 but the answer is wrong.
     
  2. jcsd
  3. Aug 29, 2005 #2

    Integral

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    RECALL:
    F=ma

    No force, No acceleration. As soon as the bolt seperates from the sting the force ends.
     
  4. Aug 29, 2005 #3

    HallsofIvy

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    Do you know what acceleration means? Initial speed was 0 m/s, final speed was 124 m/s. (124- 0)/x sec= 193 m/sec2. What is x?

     
  5. Aug 30, 2005 #4

    Mk

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    So why are you firing medieval weapons in space?
     
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