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Homework Help: The least constant acceleration

  1. Sep 6, 2006 #1
    OK, heres the problem:
    A large plane needs to get to a speed of 360 km/h on it's runway in order to take off. The runway is 1.8 km long. What would be the least constant acceleration required to take off?

    Physics just started, I need shock paddles to get me going again :surprised

  2. jcsd
  3. Sep 6, 2006 #2


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    Please show your own work. You must at least have some idea as to what equations to use?
  4. Sep 6, 2006 #3
    Would it have to have a constant acceleration of 200 km/h to reach it's top speed by the end of the runway, or am I missing something? :cry:
    Last edited: Sep 7, 2006
  5. Sep 7, 2006 #4
    Well, I divided 360 km/h by the distance, 1.8 km, and got 200. Is that the least constant acceleration needed to take off? I'm very confused.
  6. Sep 7, 2006 #5


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  7. Sep 7, 2006 #6
    So I think the next thing I need to do is figure out the time it takes to reach that speed along that distance. So what was this 200 I was getting? 200 km/h?

    I have the speed, I have the distance, how do I find the time it took to do this, or am I going off course?
  8. Sep 7, 2006 #7


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    [tex] v^2 = u^2 +2as [/tex]

    and rearrange for acceleration, a.
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