Page 23 - Curriculum Visions Dynamic Book

Glass with a “silvered” back, such as in a car mirror (below) or the solar reflectors (above), is used for the reflecting properties of the metal. The glass is simply a support that also prevents the metal from tarnishing.
from soda will fit in the space in the dissolved silica glass structure, and so soda lime glass is actually denser than natural crystal.
Glass is known for its brittleness. But it is not entirely brittle and will bend a little, as you will notice if you see people carrying a large pane of glass. This
is known as elasticity. In fact, most glass bends a little, for example, a windshield glass bends under the pressure of the wind as a car moves at speed. Glass
will twist and stretch as well as bend, but again, only a little.
If most materials are pulled or twisted further, they will change shape
and not go back to their starting point. This is called plasticity. Finally, if the material is bent, twisted, or stretched enough, it will break. Glass is unusual
in that it goes almost immediately from its elastic state to breaking. It has
almost no plasticity.
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