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Homework Help: What is the maximum height reached by the rocket?

  1. Sep 23, 2004 #1
    Could someone please help me do this question, at least parts B and C?? I already know that the max height is 281.66 m. Thank you!

    A model rocket is launched straight upward with an initial speed of 49.5 m/s. It accelerates with a constantupward acceleration of 1.83 m/s^2 until its engines stop at an altitude of 132.0 m.
    A.What is the maximum height reached by the rocket?
    B.How long after lift-off does it take for the rocket to reach its maximum height?
    C.How long is the rocket in the air
  2. jcsd
  3. Sep 23, 2004 #2


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    This should get you started:
    [tex]h(t) = v_0 t +(a-g)t^2/2[/tex]
  4. Sep 23, 2004 #3
    B) Find the final velocity reached after 132.0 m of travel, then, ignoring air friction, use that as intitial velocity, factor in acceleration due to gravity, and remaining distance to travel, and find time for the second section (engine off) of the trajectory. Now go back and use a similar formula to find the time taken for the first section (engine on).
    C) Add all your times together (don't forget its freefall motion as it falls back down)
  5. Sep 24, 2004 #4
    thank you!

    thanks so much :)
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