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ghoti
owner for sale by house
 
Join Date: Apr 2005
Location: Charlotte, NC
 
2006-09-15, 14:07

There are two effects here. As billybobsky pointed out, when you knead the eraser, the graphite gets distributed throughout its volume, so statistically it is much less likely to see the graphite particles on the surfaces. And since the volume is so much larger than the surface, it looks like they disappeared completely. Also, the particles are very small, so you will only see them when there are lots of them in the same spot.

The second thing is the hardness/softness of the eraser. This is simply due to the fact that it consists of very long molecules. These are woven into each other, and cannot react very fast. There is a toy that consists of a very similar material that will bounce around like a rubber ball, but can be shaped by kneading like one of these erasers. If you apply pressure slowly, the molecules will have time to untangle and move, but fast movements will be met by resistance. A higher temperature (from your hands) also helps, because it makes the molecules move around more by themselves. That is why the eraser gets softer the longer you play with it.

As for the taste ... haven't tried that
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