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Question Related to Newton's Laws of Motion

  1. Jul 21, 2011 #1
    1. A fully loaded Saturn V rocket has a mass of 2.92 x 10^6 kg. Its engines have a thrust of 3.34 x 10^7 N.

    a. What is the downward force of gravity on the rocket at blast-off?
    b. What is the unbalanced force on the rocket at blast-off?
    c. What is the acceleration of the rocket as it leaves the launching pad?


    m = 2.92 x 10^6 kg
    F= 3.34 x 10^7 N


    a. F?
    b. F?
    c. a



    how do you solve this question? Or can someone explain it in more detail. Also, when it says "Its engines have a thrust of 3.34 x 10^7 N" does the value represent the force applied upward?
  2. jcsd
  3. Jul 21, 2011 #2


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    Staff: Mentor

    Yes. That's the upward force. The downward force is just the weight due to gravity. What is the acceleration due to gravity g = _____ and how can you use that number with the mass of the rocket to get the force due to gravity?
  4. Jul 21, 2011 #3


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    Homework Helper

    Yes the thrust is the upward force. What is the downward force acting on the rocket? (This is what they are asking you in part a).
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