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Homework Help: Help Plz

  1. Apr 8, 2005 #1
    http://img156.exs.cx/img156/3825/22ls.jpg

    Heya!

    I just need a kick start on those questions means just which equations to use. Ty for any help! :tongue2:
     
  2. jcsd
  3. Apr 8, 2005 #2

    xanthym

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    Science Advisor

    SOLUTION HINTS:
    #8:
    Since there is no friction and no other forces acting on the bead in its direction of motion, Conservation of Energy can be used:
    {Initial Total Energy} = {Total Energy at Point A}
    ::: ⇒ {Initial Kinetic Energy} + {Initial Potential Energy} =
    = {Point A Kinetic Energy} + {Point A Potential Energy}
    ::: ⇒ {0} + {m*g*h} = {(1/2)*m*v2} + {m*g*(2*R)}
    Solve above equation for "v".
    Then the total Centripetal Force on the Bead at Point A will be "{m*v2/R}".

    #10:
    Use Conservation of Momentum applied to the System of 2 persons:
    {Initial Momentum} = {Final Momentum}
    ::: ⇒ {0} = (mperson_1)*(vperson_1) + (mperson_2)*(vperson_2)
    Solve for the ratio "(mperson_2)/(mperson_1)".


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    Last edited: Apr 8, 2005
  4. Apr 8, 2005 #3
    ty soo much!!

    of couse #8 was but tough but hmm it seems 10 is simple! :p
     
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