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Popeye throwing himself thru the air

  1. Jul 26, 2005 #1
    There is a man attached to a relatively long string with a steel ball
    on the other end. This man we will call "Popeye", is strong enough to
    lift the ball and throw it up:

    1. What's the relation between forces, speed, mass, to make the ball
    drag Popeye up thru the air? There are only basic arguments in this
    equation, no ellastic string, Popeye's body is not broken, etc...
    maybe there is some air drag, if useful.

    2. How could Popeye solve how much force he needs to throw his system X meters up?

    Now that Popeye is flying, he climbs the string and takes the steel ball:

    3. Did Popeye modify the speed of the ball by climbing the string? I
    think climbing slower or faster would make different results, but not

    4. Is there a way Popeye can control the direction of his flying
    system? How could he do that?

    5. Is it possible for Popeye to accelerate his system? How? Would it
    help cutting the string?

    I was thinking, what happens if Popeye changes the steel ball for a
    Gyroscope? Would that help in any way to maneuver?
  2. jcsd
  3. Jul 26, 2005 #2
    A) The mass of the ball will have to be very large compared to the mass
    of Popeye so that the center of mass of the two will essentially be that
    of the ball. This is confirmed to be the case because Bluto has no trouble
    lifting and swinging Popeye about.

    B) Popeye will have to have superhuman strength to lauch a ball many times
    his own weight and at high speed.

    C) Climbing the string won't change the speed of the center of
    mass of Popeye/ball.

    D) He can't control it once he launches it.

    E) He can't do anything to accelerate himself- unless he has a can of Spinach.
    He can hurl the can and get a small boost. But since he's Popeye, he can
    eat the spinach and use his pipe as a massive turboprop to achive immense

    F) Gyroscope? Yikes. Let Bluto try that one first.
    Last edited: Jul 26, 2005
  4. Jul 26, 2005 #3
    lol, thanks!
  5. Jul 27, 2005 #4
    a. The mass could be small, but the initial speed needed should be bigger.

    b. yes it is true for super human ^^, but not for the mass as the force is big, if the mass is small the speed will be more and vice versa. the mass and speed relate to each other (as long as bigger then zero for both) and the value that matter is only the force (direction of throwing would also matter actually)

    c. that's true

    d. yes he can, by how an asronote could 'move' when lost in space. By throwing things (not attched to the system after throw) around. example by cutting the string and throw the ball.

    e. the same as [d.] just make sure he throw at the correct direction

    f. abstain
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