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I really don't get this question

  1. Sep 30, 2012 #1
    1. The problem statement, all variables and given/known data

    A supersonic jet flying at 160 m/s is being
    accelerated uniformly at 23.7 m/s for 20 s.
    What is its final velocity?
    Answer in units of m/s

    2. Relevant equations
    V(final) = V(initial)^2 +2ad. Well thats what I tried using but we just started this topic and Im not sure at all.




    3. The attempt at a solution
     
  2. jcsd
  3. Sep 30, 2012 #2

    Doc Al

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    Staff: Mentor

    Since you don't have distance, that won't help. But what's the most basic definition of acceleration?
     
  4. Sep 30, 2012 #3
    The rate that velocity changes
     
  5. Sep 30, 2012 #4

    Doc Al

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    Good. Express that mathematically.
     
  6. Sep 30, 2012 #5
    v=d/t
     
  7. Sep 30, 2012 #6

    Doc Al

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    That's velocity. What about acceleration?
     
  8. Sep 30, 2012 #7

    Doc Al

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  9. Sep 30, 2012 #8
    oh right I think i got it. vf-vi/t
     
  10. Sep 30, 2012 #9

    Doc Al

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    Staff: Mentor

    Good! a = (vf - vi)/t.

    So, reverse that around and solve for vf.
     
  11. Sep 30, 2012 #10
    thanks i got it
     
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