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Homework Help: Vertical motion with constant acceleration

  1. Sep 16, 2008 #1
    1. The problem statement, all variables and given/known data
    A research balloon of total mass 410 kg is descending vertically with a downward acceleration of 1.0 m/s2. How much ballast must be thrown from the car to give the balloon an upward acceleration equal to 1.6 m/s2, presuming that the upward lift of the balloon does not change.


    2. Relevant equations
    B-w=m*a
    w=mg

    3. The attempt at a solution

    w= 410*9.8
    w= 4018 N

    B-4018 = 410*-1
    B=3608

    3608-m{2}*9.8= m{2}*1.6
    2255= m{2}+9.8m{2}
    2255= 10.8m{2}
    m{2} = 208.80
    410-208.80= 201.2kg
     
  2. jcsd
  3. Sep 17, 2008 #2

    PhanthomJay

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    Science Advisor
    Homework Helper
    Gold Member

    Your method is good. Check your math error as noted above.
     
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