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I'd want to play marbles....for the first time forty years or so.....[+] |
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You played marbles in your 20s?! |
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One small change I'd make: turn them on when they're shaken, not when it's dark. (Otherwise, they'll spend most of their life glowing to themselves inside a package or bag.) Something like that already exists in bouncing rubber balls with embedded LEDs. |
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This is cool - no idea why it isn't sold yet. |
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Yes, impact sensors could indicate which marbles had been hit while playing. |
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To add to the fun, there are some new technologies a-comin' down the pike that scavenge vibration and general kinetic energy to generate tiny amounts of electrical power when an item is moved, hit or jiggled. So there's no need for a battery at all - the light goes on as the marble is used, and when it's quiescent, it stays quiescent. How Newtonian! |
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An excellent concept and a more fodder for playground oneupmanship. However, marbles are made by melting glass down and rolling it (see link) so
how do we get the LED inside? |
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Mold 'em, mold 'em / Shake 'em and hold 'em / Put 'em in the dark and then / Watch 'em glow golden |
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Molten glass is very hot. My guess is that even considering the small amount of glass required, there would be enough heat present to damage the LED and battery. This would result in a high failure rate, driving the cost up and making them playthings only for the very rich. Inevitably, a dual-tier toy system would arise, resulting in class-division, economic upheaval, probably famine. |
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//Molten glass is very hot.// |
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Hmm. You could still do this by gluing together two glass hemispheres, with the electronics embedded in clear resin in the middle. |
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Actually, what's the lowest-melting glass? People have developed plenty of low-melting metal alloys, why not glasses? |
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Possibly, but you want the density, scufflessness and clickiness of glass. |
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//I held my ipad up behind it (to act as a polarised light source) and held my polarising ray-bans up in front of the glass// |
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That is clever - will have to try. |
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Cool! I wonder if my pair of 3D polarizing glasses will work? |
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[MaxwellBuchanan], your 3D movie glasses are (probably) a
left- and a right-handed pair of circularly polarised lenses;
what you want is proper linearly polarised sunglasses. |
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You're probably right. Rotating them in front of my screen causes the image to brighten/darken only by maybe 50%. If I look at my old LCD calculator through them, one lens change the background brightness by 100% depending on rotation, while the other lens has no effect. |
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I am beginning to suspect that I actually know much less about polarization than I thought I did. In particular, if vertically polarized light has the electric field wobbling up and down; and horizontally polaried light has the field wobble left and right; then what in gods' names does circularly polarized light do?? |
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(Getting some-what off-topic...) polarisation of light is a
messy business (see linky). I'm not entirely sure I understand
it myself (even after doing a reasonable amount of optics at
university).
It is one of the reasons I am a fan of the "two-particle
photon" theory (linky). |
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Do circular polarisers come in clockwise and
anti-clockwise variants? |
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//I am beginning to suspect that I actually know much
less about polarization than I thought I did.// |
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The explainations I have seen, heard or read don't
make 100% sense to me. I suspect that either a: they
don't know everything and it falls into that chunk of
physics that they can describe very well, and make
useful things using the descriptions but.... b: its
almightily complex stuff and we're in the: "look, 2
electrons in the first little planet orbit, 8 in the next
one, and... no, don't ask why..." area of partial
ignorance. |
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The way I understand it is that there are minerals
through which light travels at different speeds
depending upon what angle light hits it, because of
crystals and things we have a fast axis and a slow axis
through the mineral. I'm totally OK with that. Two
photons, one perfectly aligned with the "fast" axis one 5
degrees off. Second one comes out slightly after the
first, I am perfectly happy with that. You have two
photons describing two points of a helix 5 degrees
apart, the pitch of the helix dependent upon the
relative delay introduced by the material. This is where
I get confused. If I hit the material with light PERFECTLY
polarized in the vertical plane, how can any rotation be
induced? Each photon will travel through with the same
speed. I understand that creating perfectly polarized
might be difficult/impossible, but does that mean my
circularly polarized helix is actually a messy thing with
tremendous differences in relative light energy
dependent on the degrees off-plane? Come to think of
it, I'm not sure how a single photon gets refracted by a
prism, unless different parts of the same oscillation can
have different speeds... I'm now more confused than I
was before. |
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At the subatomic level, nothing describes reality
because all our reference concepts are so 'macro'.
Any description we use is just a model ("It's only
a model...") which we use because it has some
prescriptive power in a narrow range of
applications. So, we might use the 'particle' model
of an electron one day, and then the next day, for
another purpose, use the 'wave' model of the
electron. That's fine, as long as we recognise
these are just models, which we use because they
give us some words to talk about things with. |
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