Childhood lies. What do you still hold up as the truth??
Discussion
Glass is not a liquid in the strictest sense of the word, but it's also not a standard solid. Instead, scientists describe glass as an amorphous solid, a state of matter that's between a solid and a liquid. Glass is more organized than a liquid, but not as organized as a crystal, and it lacks the ordered molecular structure of true solids.
Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
bobtail4x4 said:
For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries.
Sadly not.https://gizmodo.com/the-glass-is-a-liquid-myth-has...
https://streetscience.com.au/is-glass-a-liquid/
https://ceramics.org/ceramic-tech-today/glass-visc...
bobtail4x4 said:
For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries.
I had a business meeting with a Lab manager at a leading glass manufacturer and he hold me that this is false. He said that the glass is thicker at the bottom of old windows only because of the old technique they used to manufacture sheet glass. bobtail4x4 said:
Glass is not a liquid in the strictest sense of the word, but it's also not a standard solid. Instead, scientists describe glass as an amorphous solid, a state of matter that's between a solid and a liquid. Glass is more organized than a liquid, but not as organized as a crystal, and it lacks the ordered molecular structure of true solids.
Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
In the past, when panes of glass were commonly made by glassblowers, the technique used was to spin molten glass, creating a round, mostly flat plate ( https://www.britannica.com/technology/crown-glass). This plate was then cut to fit a window. The pieces were not, however, absolutely flat; the edges of the disk became a different thickness as the glass spun. When installed in a window frame, the glass would be placed with the thicker side down both for the sake of stability and to prevent water accumulating in the leading at the bottom of the window. Occasionally such glass has been found with the thinner side down due to carelessness of installation.Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
This production method also explains 'bullseyes' seen in old windows.
bobtail4x4 said:
Glass is not a liquid in the strictest sense of the word, but it's also not a standard solid. Instead, scientists describe glass as an amorphous solid, a state of matter that's between a solid and a liquid. Glass is more organized than a liquid, but not as organized as a crystal, and it lacks the ordered molecular structure of true solids.
Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
Good explanation, a teacher once described glass as a liquid frozen in time.Glass is made by quickly cooling a liquid that often contains silica, which turns it into a supercooled liquid. As the liquid cools further, its viscosity increases, and it eventually transitions into an amorphous solid below the glass-transition temperature. This process gradually slows the movement of molecules, retaining the structural disorder of a liquid but giving the glass the physical properties of a solid.
On a short timescale, glass can appear solid, but over time it can slowly flow, similar to thick syrup. For example, the bottom of stained glass panes in old churches are often thicker than the top because the glass has flowed down over centuries. At lower temperatures, the relaxation time of glass can reach millions of years, making it effectively solid for all practical purposes.
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