No physics classroom is complete without chalk, but let's face it, dry erase pens and boards are here to stay. The solution? Dry Erase Chalk! a stick composed of microscopic sealed bubbles of dry erase ink. when you write on a compatible dry erase board, the bubbles rupture, releasing ink,allowing one to write on a dry-erase board, with the familiar "stik-o-chalk" These could be available in an even wider range of colors than chalk, and could potentially make a cool popping noise when used!-- whatastrangeperson, Mar 31 2004 Why, exactly?-- DrCurry, Mar 31 2004 Why not? There wasn't any reason to revive the VW Beetle, except fond memories.
A stick of dry erase chalk would have the added benefit, compared to a dry erase pen, that you can share it without giving away the whole thing. Break off a piece and it still writes.I don't know about the popping noise. Chalk never popped for me. However, the full kit should come with a little "screechy" device that allows the user to make the appropriate noises while writing.-- kbecker, Mar 31 2004 I'm not quite getting what releases the ink. Just the pressure applied while writing? I don't see how it could be rigid enough to write with in that case. Then again, I'm not terribly bright.
I can see maybe making a dry erase marker with a "chalk chuck" on one end to hold a piece of chalk that corresponds to the color of the marker.-- half, Apr 01 2004 [half]-the rupture of the sealed bubbles of ink will release the ink, they will be made to rupture when applied to a surface, and the constant rupture of the bubbles might make a cool noise.-- whatastrangeperson, Apr 01 2004 Wouldn't your grip then also rupture the bubbles since the force applied againt your hand is the same as that applied to the chalkboard? And if your solution to that is to wrap something around the chalf to protect it from your grip, is that not just like a marker anyway?-- Nitehawk, Apr 01 2004 I was wondering what the structure would be like. Anything that would rupture by such light pressure seems like it wouldn't have much stiffness in a cylindrical form.
And if it does work, structurally, how do the layers of dead cells get removed from the surface to expose more ink-laden cells?
The pressure from holding it didn't even occur to me.
(btw - my standard disclaimer: if it was truly workable it probably wouldn't be here, but that doesn't stop me from asking questions as if we're discussing an actual product under development. That's what keeps the place interesting to me.)-- half, Apr 01 2004 It could be made friction-sensitive instead of pressure-sensitive to avoid the grip problem.-- Random832, Mar 28 2005 random, halfbakery