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Homework Help: I dont know if I did the problem right check please.

  1. Feb 4, 2008 #1
    [SOLVED] I dont know if I did the problem right check please.

    1. The problem statement, all variables and given/known data
    A jet is diving vertically downward at 1200km/hr
    the pilot can withstand a maximum acceleration of 4G, before losing consciousness, at what height must the plane start a quarter turn to pull out of the dive? Assume the speed constant.


    2. Relevant equations

    A=V^2/r

    3. The attempt at a solution

    for this circular motion we know that h = radius of the circle
    so
    4G=(1200km/hr)^2/h
    4G=4*9.8m/s=39.2m/s=508032km/hr^2(Not sure if convert it right)
    508032=1200^2/h
    h=2.834Km
    Is this right, the answer has to be in Km so I convert the 4G.
     
  2. jcsd
  3. Feb 4, 2008 #2

    Shooting Star

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    If you want the ans in km/hr, convert everything to those units.

    4g = v^2/h =>
    4*(9.8/1000)/(1/3600)^2 = 1200^2/h. The value of h will be in kms.

    EDIT: 1/3600 corrected (1/3600)^2, after being pointed out by yaho8888.
     
    Last edited: Feb 4, 2008
  4. Feb 4, 2008 #3

    PhanthomJay

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    Looks good; you incorrectly typed m/s instead of m/s^2 in your 4G calculation, but the math came out OK.
     
  5. Feb 4, 2008 #4
    wouldn't that be 4*(9.8/1000)/(1/3600)^2
     
  6. Feb 4, 2008 #5

    Shooting Star

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    Yes. Thanks for pointing out the typo. I'll edit the post.
     
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