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Posers and Puzzles

Posers and Puzzles

  1. Subscriber sonhouse
    Fast and Curious
    23 Apr '15 12:06
    If you assumed standard atmosphere, pressure and room temperature, so you don't need a space suit, how high could you jump on Ceres?

    The surface gravity there is about 0.27 m/s^2.
  2. Standard member forkedknight
    Defend the Universe
    23 Apr '15 20:44 / 1 edit
    First, let's assume that on earth, I can jump ~ 2ft, or 0.6m high.

    Using equations for conservation of energy, we can determine my jumping velocity (really my landing velocity):

    m*g*h = 0.5*m*v^2
    or
    v^2 = 2gh

    Since g on earth is 9.8m/s^2, and my jump height is 0.6m

    v^2 = 11.77 (m/s)^2
    v = 3.43 m/s

    Using the same equation in reverse to get my jump high on Ceres

    11.77 = 2 * 0.27 * h
    h = 21.8m
  3. Subscriber sonhouse
    Fast and Curious
    26 Apr '15 21:22
    Originally posted by forkedknight
    First, let's assume that on earth, I can jump ~ 2ft, or 0.6m high.

    Using equations for conservation of energy, we can determine my jumping velocity (really my landing velocity):

    m*g*h = 0.5*m*v^2
    or
    v^2 = 2gh

    Since g on earth is 9.8m/s^2, and my jump height is 0.6m

    v^2 = 11.77 (m/s)^2
    v = 3.43 m/s

    Using the same equation in reverse to get my jump high on Ceres

    11.77 = 2 * 0.27 * h
    h = 21.8m
    What about the best humans can do? I think the present record is a bit over 8 feet! 2.44 meters! Would it be linear, since that would be 4 times higher, so Would that come out to 87.2 meters on Ceres?
  4. Subscriber joe shmo
    Strange Egg
    26 Apr '15 23:35 / 1 edit
    Originally posted by sonhouse
    What about the best humans can do? I think the present record is a bit over 8 feet! 2.44 meters! Would it be linear, since that would be 4 times higher, so Would that come out to 87.2 meters on Ceres?
    To answer your question...yes the relation ship is linear. However, as it is, the equation is only good for vertical leap. That limits it it to standing still, and jumping without changing your body's center of mass with respect to the extended body. I don't think anyone has a true vertical leap of 8 ft here on earth.
  5. 17 May '15 03:09
    If we consider that we could be assisted with our jump we can get even higher. The escape velocity on Ceres is reportedly 510 m/s. If we decide to not exceed 500 m/s to avoid an error in the escape velocity number then we get a height of:

    500 / (2 * 0.27) = 926 m (rounded)

    That same apparatus on earth would only get us 25.5 m [5 giraffes - see below], which is an impressive jump but gives you the idea of the escape velocity. Most people with a reasonably good arm can throw a ball this high, so we could stand on Ceres and 'throw' ball-massed satellites into orbit. That would save on gas! (https://what-if.xkcd.com/44/)
  6. 17 May '15 20:00
    Would it be part jump and part push as Ceres would move away from us.
  7. 17 May '15 22:28
    Originally posted by divegeester
    Would it be part jump and part push as Ceres would move away from us.
    Of course that is always true, but the momentum imparted to Ceres would be very small. Ceres has a mass of approximately 895.8E18 kg, whilst an average human has a mass of 80.7 kg. That is a HUGE difference and Ceres would move an very insignificant amount.
  8. Subscriber sonhouse
    Fast and Curious
    19 May '15 12:23
    Originally posted by GastelEtswane
    If we consider that we could be assisted with our jump we can get even higher. The escape velocity on Ceres is reportedly 510 m/s. If we decide to not exceed 500 m/s to avoid an error in the escape velocity number then we get a height of:

    500 / (2 * 0.27) = 926 m (rounded)

    That same apparatus on earth would only get us 25.5 m [5 giraffes - see ...[text shortened]... row' ball-massed satellites into orbit. That would save on gas! (https://what-if.xkcd.com/44/)
    Job listing for the year 2145: Ceres needs people with good throwing arm to launch small payloads from surface, baseball pitchers may apply. Good working conditions, sign on bonus, one month vacation per year, very high salary...
  9. 19 May '15 21:46
    Originally posted by sonhouse
    Job listing for the year 2145: Ceres needs people with good throwing arm to launch small payloads from surface, baseball pitchers may apply. Good working conditions, sign on bonus, one month vacation per year, very high salary...
    Only Ceres-ious applicants should apply?
  10. Subscriber sonhouse
    Fast and Curious
    20 May '15 18:39
    Originally posted by GastelEtswane
    Only Ceres-ious applicants should apply?
    Good one