19 February 2009

Plasticine – what it’s like

Take a look at this…..

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What’s it like?

Well (apart from its greenness) it is cool and quite hard, although if you dig your fingernail into it, you will leave a mark.

Ok.  Now roll it into a ball.

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Not easy, is it?  But beaver away.  Squash and squish it.

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Roll it round and round.

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Pull it; tug it; stretch it.

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Roll it into a long snake.

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A longer snake.

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An even longer snake.

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What do you notice about its texture now?  About its temperature?  (Remember how one of the places most sensitive to temperature is just above your lip.)

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Are the properties the same now as they were when we began?

No – now the plasticine is warm and soft and no longer cool and hard.  Easy to squish into a ball.

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Incidentally.  The word plasticine has a bit of a clue.  But have you ever thought about what materials plasticine is made from?

Plastic; a man-made material made from oil.  Plasticine; a man-made material with petroleum jelly (petrol; oil) as one of its ingredients.

So, what’s it like – plasticine?

Apart from being something that makes your hands go red…..(or blue or green)

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More to the point; what can it be used for?

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