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Minimum Rate of Rocket Fuel Consumption

  1. Nov 23, 2013 #1
    1. The problem statement, all variables and given/known data

    A rocket which has an exhaust speed of 8.0 km/s is to have a vertical acceleration of 8.0 m/s2. If the initial mass of the rocket is 6.0x106 kg, at what minimum rate must the rocket consume fuel?

    2. Relevant equations

    F = ma
    F = RVREL

    3. The attempt at a solution

    F = (6.0x106 kg)(8.0 m/s2) = 4.8x107 N

    R = (4.8x107 N) / (8000 m/s) = 6000 kg/s.

    The back of the book tells me this answer is wrong. I would appreciate any insight into the error(s) I am making.

    Thank you!
  2. jcsd
  3. Nov 23, 2013 #2


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    I think you must apply Newton's Second Law to the rocket as it lifts off. Your F value is F(net) and not the actual thrust produced by the rocket motor.
  4. Nov 23, 2013 #3
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