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Ways to lighten things

  1. Feb 21, 2013 #1
    Got any idea that can make a things lighter while it is moving? Like making a thing lighter on bicycle so that we can save more energy
    Last edited by a moderator: Feb 21, 2013
  2. jcsd
  3. Feb 21, 2013 #2

    Simon Bridge

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    Remove bits and throw them away.

    Usually you try to minimize things like weight during the design stage - i.e. before you start moving.
  4. Feb 21, 2013 #3


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    Our friend who is confined to a wheelchair said he’d love to go with us into the Angeles National Forest on a weekend hike. Since we are all engineers we made a plan to “lighten the load”. We got several heavy-duty weather balloons, some strong nylon net, fashioned a helium-filled lifting body, and attached it to his wheelchair. When we arrived at the trail we added helium from a chair-mounted tank to the balloons until his total weight was around twenty pounds. We then carried him along on our trek through the wilderness. As we travelled further we added more helium to the balloons to make him even lighter. Our friend enjoyed his day in the wilderness.

  5. Feb 21, 2013 #4

    Simon Bridge

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    @bobbywhy: LOL
  6. Feb 25, 2013 #5
    Roflmao thats one way to lighten the load lol
  7. Feb 25, 2013 #6

    Simon Bridge

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    @Apache: you are getting funny answers because you presumably know already that to lighten the bike you need to use light materials ... thus: your question is too general.
    If you tell us what you are trying to do in more detail it may help. What is the actual problem you are trying to solve? i.e. what are you anticipating happening while the bike is moving that would require you to make it lighter on the fly like that?

    Everything I can think of would make the bike more massive overall.
    you could include a hot-air balloon and burner ... when you need to be lighter, switch the burner on or drop sand-bags;
    attach rockets where the carrier bags go - then you can lose mass and gain momentum too;
    (for that matter - any engine will have you lose mass turning fuel into exhaust);
    install ejector seat - remove that heavy pillion passenger (or the driver) at the press of a button;
    carry tools - then you can cut off, drill out, and unbolt inconvenient bits ... if you include surgical tools the rider can be included in this;
    ... all these things add to the start mass so I'm guessing it's not the sort of thing you want.
    Last edited: Feb 25, 2013
  8. Feb 25, 2013 #7
    In line with what everyone else is saying:

    You can't reduce the mass of a thing without removing some of it's parts (like a hot air balloon dropping sand bags) so the only way to make something weigh less, is to counter the force of gravity acting on it. Planes do this with wings, Balloons do this with low-density gasses (or reducing the density of a gas via temperature change) to create a boyancy force.
  9. Feb 28, 2013 #8
    Finally I reduce my weight by using lighter materials yet affordable price for my design..
    since it is hard to create buoyancy force or any pressure difference between my devices on my bicycle!
    Thanks you all!
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