Velocity-time graph for a rocket

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  1. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    Velocity-time graph for a rocket
    Please look at the question attached.
    Why is the answer C?

    thanks

    ----
    here is the only answer I can think of:
    the further away the rocket is from earth the smaller its gravitational attraction to earth. Therefore the greater the resultant force (away from earth) so its acceleration increases rapdily

    is this correct?
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  2. siwelmail's Avatar
    • Overlord in Training
    • Location: England
    • Posts: 3,324
    Re: Velocity-time graph for a rocket
    There is other stuff in space BTW
  3. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    Re: Velocity-time graph for a rocket
    (Original post by siwelmail)
    There is other stuff in space BTW
    so then why is it C??
  4. It.'s Avatar
    • Junior Member
    • Posts: 35
    Re: Velocity-time graph for a rocket
    I would say you were correct, as the force from the rocket is constant, and the gravitational attraction from the earth decreases with distance. F=ma, so acceleration increases as resultant force increases.
  5. siwelmail's Avatar
    • Overlord in Training
    • Location: England
    • Posts: 3,324
    Re: Velocity-time graph for a rocket
    (Original post by ilovemath)
    so then why is it C??
    Velocity= Displacement from start/time.

    Work it out yourself with words, relating to the rocket.
  6. Stonebridge's Avatar
    • Community Assistant
    • TSR Demigod
    Re: Velocity-time graph for a rocket
    (Original post by ilovemath)
    Please look at the question attached.
    Why is the answer C?

    thanks

    ----
    here is the only answer I can think of:
    the further away the rocket is from earth the smaller its gravitational attraction to earth. Therefore the greater the resultant force (away from earth) so its acceleration increases rapdily

    is this correct?
    Yes. That's the reason why the answer is C.
  7. ilovemath's Avatar
    • Benevolent Member
    • Posts: 730
    Re: Velocity-time graph for a rocket
    (Original post by Stonebridge)
    Yes. That's the reason why the answer is C.
    thanks
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