• Matombo@lemmy.world
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    2 months ago

    Fun at partys guy: While the car will actually experience a force torwards the magnet, so will the magnet experience an equal amount of force torwards tha car. Given the connection between the car and the magnet is stiff, these opposing forces will stress the connection and create a reactive force in there according to Newtens 3rd law, ultimatly canseling the forces out and neither the car nor the magnet will move.

    If you however remove the stiff connection, the car and the magnet will move torwards each other untill they meet.

    • affiliate@lemmy.world
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      2 months ago

      what if you just attach a second magnet to the car so that it pulls the first magnet forwards?

    • voodooattack@lemmy.world
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      2 months ago

      How about if you launch a huge magnet well above escape velocity and remotely anchor a space elevator made from a ferromagnetic material to it but the space elevator’s weight counteracts its inertia exactly and holds it in place perpetually. Would that work?

      Edit: I swear I’m not dumb, I just didn’t think this one through.

  • credo@lemmy.world
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    2 months ago

    It will, but why do you want the truck to attract the magnet? Are you going to drive backwards everywhere?

  • regdog@lemmy.world
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    2 months ago

    This illustration does not imply that the car is moving. There are no “speed lines” or arrows that would indicate that.

    So the illustrated setup would 100% work.

  • Pleb@feddit.de
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    2 months ago

    Good old troll physics.

    W…wait, why is the troll head missing?!?

  • prime_number_314159@lemmy.world
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    2 months ago

    I built a scale model to prove the haters wrong. I had to tilt the platform a little for it to overcome friction, but once I did, the car rolled forward until it hit a wall.

        • GoodEye8@lemm.ee
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          2 months ago

          Depends on what we consider wrong. Could you pull a car that way? Theoretically, yes. Could you save energy that way? No, because the car driving in front would have to do extra work to overcome the magnet pulling it towards the car behind. You can’t cheat the first law of thermodynamics.

          • Feathercrown@lemmy.world
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            2 months ago

            But that’s not my energy, the guy in front now has to pay for me to be his trailer.

            Also unmeme for a second, wasn’t there news that we were able to harvest energy from brownian motion about a year ago? What happened with that?

    • Rakonat@lemmy.world
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      2 months ago

      Use two magnets of opposing polarity, the stronger magnet should be on the bumper to push the boom forward, and drag the truck with it. /s

  • snooggums@midwest.social
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    2 months ago

    Because both of the magnet’s poles are pointed at the car and the attraction and repulsion are canceling each other out.

  • idunnololz@lemmy.world
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    2 months ago

    It’s actually a common misconception that magnets always attract metal. This misconception was popularized by people joking that magnets are magic. In reality, magnets attract because they have magnetions in them. These magnetions allow them to attract things like metal but a little bit is used up each time. Eventually once the magnet’s magnetions have been depleted, the magnet turns back into a newt and goes home to recharge.

  • MentalEdge@sopuli.xyz
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    2 months ago

    This is actually kind of how electric motors work as the rotor chases a magnetic field forever kept out of reach by the stator, and you can’t tell me otherwise.

    • FuglyDuck@lemmy.world
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      2 months ago

      The difference is, that the rotor is allowed to move, and they’re switching coils in the stator to keep it going.

      In this system, the force pulling the magnet towards the truck is being negated by the arm fixed to the truck.

      If you placed a bunch of electromagnets on the guard rail, that would be more like a motor (technically, a linear motor,)

  • LemmyKnowsBest@lemmy.world
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    2 months ago

    because the truck is self-propelled, and it can only go as fast as it takes itself. Therefore the magnet, which is attached to the truck, can only go as fast as the truck takes itself.