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Homework Help: Calculate the thrust acting on a rocket

  1. Nov 22, 2012 #1
    1. The problem statement, all variables and given/known data
    A 20,000 kg rocket exhausts gasses at a constant 700 kg/sec at 300 ms^-1
    Deduce the thrust applied to the rocket by its engines

    2. Relevant equations

    The only equation I know is a= T- mg/m

    Where T= thrust
    a=acceleration
    m=mass

    3. The attempt at a solution
    I don't know any other formulas and I can't use the one above because I don't have the acceleration
    Please help??
     
  2. jcsd
  3. Nov 22, 2012 #2

    HallsofIvy

    User Avatar
    Science Advisor

    Use "conservation of momentum". You can calculate the momentum of the exhaust gases from the information given and that must be equal to the momentum of the rocket itself. What thrust will give that mometum?
     
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