Points at the beakers on the screen
Lucy: So, if you cool it down. Yeah it probably is water.
I think it would, urn, because if you go up to the top temperature its’ frozen.
So that’s how it was when I turned it on to this. When you cool it down. So it
melts.
Points at the screen [at what she thinks is a representation of solid but is
actually a liquid]/points at ‘liquid to solid’ key
The students take up the visual sign even though the writing clearly indicates that the
direction of transformation is from ‘a liquid to a solid’ and therefore what is on the
screen, for the students to look at, is a solid.
The move from the representation of a liquid as a light pale blue to a solid
represented as a heavier, stronger blue indicates the designer’s principle of the use of
colour as a marker of ‘density’, ‘compactness’ or ‘lack of movement’. Through the
semiotic resources of the saturation of colour the solid is represented as a ‘condensed’
version of the liquid. However, the students read it as an everyday sign of cold and
warm and in doing so they associate the pale colour of the liquid with the pale
translucence of ice and more generally ‘coldness’. Using the same principles the
students read the darker blue used to represent the ice as being ‘like water’ and more
generally as ‘heat’ or ‘warmness’, as being ‘warmer’. The more intense saturation of
the colour, where ‘intense’ seems to be the feature that the students have focused on,
is interpreted as ‘energy’ and ‘warmth’.
The difficulty that some of the students experience in interpreting the representation
of the transformation from a liquid to a solid is rooted in their difficulty in reading all
of the modes as meaningful. The students have to resolve a contradiction, and do so
by use of their ‘everyday’ principles. In their reading of the multimodal signs of the
screen the students rely on colour and the mode of image more than on the modes of
writing and movement to making sense of what is displayed on the screen. This can
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