• ReluctantMuskrat@lemmy.world
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    1 year ago

    I’d like to know how many rpms that is and the speed that equates to when it starts deforming and when it flies apart.

  • DreamButt@lemmy.world
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    1 year ago

    Wonder if the result would be different if you could somehow get the force applied evenly across the surface.

    • Natanael@slrpnk.net
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      1 year ago

      It would flatten out against the surface and then break similarly but out to the sides

      • LastYearsPumpkin@feddit.ch
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        1 year ago

        Watches 10 seconds gif “yeah, I know exactly what’s going on here and will confidently state my incorrect opinion as fact”

        • 🔍🦘🛎@lemmy.world
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          1 year ago

          But… You can see a divot in the center of the wheel where the string is making contact. It looks like it breaks apart because of that new weak point. It’s not like I’m being an armchair physics professor, I’m making an inference.

            • 🔍🦘🛎@lemmy.world
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              1 year ago

              You know, I wasn’t sure whether it was a water jet or not, since that’s used to cut through STONE. So, it’s likely that the wheel was being cut in half prior to it tearing apart.

              • 0ops@lemm.ee
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                1 year ago

                The ones used to cut through stone and steel typically have diamond “sand” muddying the water. At least the one at my local machine shop does. I’m guessing the one in the gif is straight water.

  • wreleven@lemmy.ca
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    1 year ago

    Lots of heat here too I suspect. The deformation is going to be way easier with all that heat from the friction.

    • Chrüsimüsi@feddit.chOP
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      1 year ago

      Angular momentum is a measure of an object’s rotation around a point (#spin) 🌪️.

      Centripetal force is the force that keeps an object moving in a circular path, always pointing towards the center (#holdingtight) 🎯.

      One is about spinning momentum, the other about the force directing that spin.

      In this example:

      As you shoot the water jet at the skateboard wheel, you are continuously adding angular momentum to the wheel. This increases the wheel’s rotational speed.

      As the wheel spins faster and faster, the individual particles in the wheel experience a greater centripetal force, pulling them towards the center of the wheel’s rotation. However, at the same time, due to the increased rotational speed, the particles also experience a greater centrifugal force (which is not a real force but an apparent force observed in a rotating reference frame), pushing them outwards.

      At a certain point, this outward “force” (centrifugal effect) becomes too great for the material of the wheel to withstand, overcoming the cohesive forces holding the wheel together, and it starts to expand and eventually breaks.

      This being said, I’m not sure if that’s actually correct what I just wrote, so take it all with a grain of salt (as one should do anyway when reading something online…)

      • FlapKap@feddit.dk
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        1 year ago

        The way I think about it is that all the individual atoms of the wheel wants to move in a straight line. The only reason the wheel doesn’t fall apart normally when it turns is that the material is strong enough to hold itself together. However as it spins faster and faster it requires more and more strength to keep itself together and at some point it moves so fast that the internal strength of the material is not strong enough to pull itself away from this straight line, which causes it to break.

      • JadenSmith@sh.itjust.works
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        1 year ago

        Heck yeah. I still have mine as backups for when my Super Swiss 6’s start grating. Been years though, these bearings are made to last that’s for sure.

        • sebinspace@lemmy.world
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          1 year ago

          I use Reds on my quad wheels. I just consider them as cost of buying new wheels because I’ll be damned if I use factory shit bearings. How are the 6’s treating you?

          • JadenSmith@sh.itjust.works
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            1 year ago

            Sorry just saw this reply!

            The SS6 bearings are insanely fast, and all my friends call them death traps as they can’t even stand on the board. 10/10 highly recommended.