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I have To Create my Own World W/O Friction HELP!

  1. Nov 1, 2006 #1
    I have To Create my Own World W/O Friction!!! HELP!

    Ok here's the deal:


    You have learned just about enough physics at this point to play god. You will now create your own world. Unfortunately, you are a lesser god and forgot one fairly basic element. Your world does not have friction. Describe your planet and its inhabitants, ie How did they evolve over time as creatures w/o friction. Explain how they move, what they look like, the structure of their homes and other buildings. Do they have hair, what clothes and food. Be very specific. Create and name your planet and inhabitants, they don't have to be humanoid and probably wouldn't be.

    Note: Earth was already created, do not use earth in the future.

    For Extra Credit: Draw your creatures

    I really am stumped on this, I don't see how something could stop w/o friction. I was thinking about having creatures that would fly but I don't know how they'd stop. Any help would be appreciated
  2. jcsd
  3. Nov 1, 2006 #2
    A world without friction...Well...If I had to do this beastly sounding assigment, I would say my "world" is one never ending movement. The planet always moves at very high speeds and my "creatures" would "fly" at extremely high speed due to no air resistance.

    Clothing: it can really be anything (no friction=no essentially no size restrictions of clothing)
    food: I would say something like "food for my creatures is never clumped and always free of contact with other foods(something like that)

    These are some suggestions. In general, no friction means no slowing down and thus, very high, continuous speeds. Domestical ideas are a little harder, but supply the following concept (or lack of the following concept) and be creative. Hope you do well with this beastly assignment.
  4. Nov 1, 2006 #3


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    It sounds like you're on the right track. See if you can come up with some mechanisms -- say, involving impacts, rubber bands or magnets, rather than friction -- by which their cars could stop.

    - Warren
  5. Nov 1, 2006 #4
    well, the creatures cannot walk....how about some sort of jet propulsion, much like a squid uses jet-like propulsion to propel through the water? These creatures could have some sort of biological propeller mechanism. The creatures could SLIDE across frictionless the surface of the planet, while being propelled by a series of props. One prop to propel the creature forward, a rudder to turn, and a prop in the front to allow for braking.

    of course for a propeller to work, you'd need air, and therefore you'd have air resistance, but you'd have to claim that there is no air resistance, somehow.
    Last edited: Nov 1, 2006
  6. Nov 1, 2006 #5


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    Here's what I make of it...

    The fundamental force responsible for friction is the electromagnetic force. As two objects come very close together, the electrostatic repulsion btw molecules and atomes (which varies approximately as [itex]1/r^n[/itex] for some power n) becomes very large and the force is felt. If you try to "slide" two object together, the irregularities in the surfaces interact together electromagnetically and this is friction.

    So without the electromagnetic force, there is no friction. But without E&M, there is also no cohesion of matter and hence no life, and hence supressing E&M is not what your instructor had in mind. The so called lesser god is actually pretty talented imo. He can supress friction but not E-M. So let's assumed He can do that but our infrerior intellects are too restricted to comprehend how He does it.

    I'm not gonna do the work for you but I recomment that you just think about things that we do/have and ask if it would still work/exist in a frictionless world. For instance, could we walk? Could the stone age people have made fire? Could they have carved arrows out of stones? etc.
  7. Nov 2, 2006 #6
    there is no material that is frictionless becuase it is impossible to get to absol zero temp hence no surface is perfect,

    it would break so many laws that this world would definitly be totally different in every respect.

    but i think your teacher was just trying to get you to think about ways you could overcome no friction.
  8. Nov 2, 2006 #7
    Thanks for the help guys.
    Last edited: Nov 2, 2006
  9. Nov 2, 2006 #8
    Here are some ideas I've come up with:

    The creatures are capable of flying.....fly like humming birds than other birds....allows them to hang in the air. They have gigantic ears that they flip us when they want to stop....acting as a horizontal parachute to help them slow down due to air resistance. They are always moving

    The vehicles they drive in have many advanced features. They have a rotating jet properler/burner thing that can rotate 360 degrees and in any direction at the bottom of the vehicle to propel the creatures in the direction they want to go. They also have a helicopter propeler on the top that allows them to hang in the air.

    The trouble I'm having is:

    I want to use the magnets....and the polarity of magnets such as attraction and repulsion...is there anyway I could explain how I would alter a such magnet to either attract or repel another magnet according to where the said creature wants to go in relation to the other magnets throughout this world. (if that makes sense)
  10. Nov 2, 2006 #9


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    I think you guys missed it. The "lungfish" step of evolution would have not been possible without friction to slither up on land. The world of this assignment would have to all be in the oceans.

    On second thought, I guess that this world is created by the lesser god, so evolution might not be a limitation after all. Hmmmm.
  11. Nov 2, 2006 #10
    Simply with electricity, you could adjust the polarity of the magnet in your car.
  12. Nov 2, 2006 #11
    What should I have these suckers eat? I know it needs to be something with a lot of carbs and that is easily accessible...but am I going to have to come up with my own creature or what? Plants won't work because they use friction in their root structure right?

    I was going to have them eat with a trunk purely using an air tube that sucks up stuff like a vaccum w/o friction.
    Last edited: Nov 2, 2006
  13. Nov 2, 2006 #12


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    Fish. But they have to dive in and bite them, since they can't catch them without friction. Well, I guess you could catch them in a basket or something....
  14. Nov 2, 2006 #13
    Would a vaccum tube wor if the air suction was very strong? Or does that use friction?

    I'm also going to say that this world has only 2/3's the gravitational pull of earth allowing objects to become suspended.
    Last edited: Nov 2, 2006
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