| Chronology | Current Month | Current Thread | Current Date |
| [Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |
Think about the atoms in the edge of the inner ring. The increased
temperature means that each on the average take of more space, but
moving in would decrease the circumference and hence force the atoms
closer together rather than further apart. Now it could happen if
the material folded. In a metal that means creating
dislocations...that takes more energy than is available, but bagels
are another thing.
Does that help...comments?
joe
Joseph J. Bellina, Jr. Ph.D.
Professor of Physics
Saint Mary's College
Notre Dame, IN 46556
On Feb 23, 2006, at 11:09 AM, Anthony Lapinski wrote:
In discussing heat, I did the ball/ring demo and many students were
surprised to see that the hole EXPANDS when the ring is heated.
It's like
expanding a photograph of a bagel -- both the inner and outer
diameters
expand. So a student today asked why actual bagels behave differently.
When the yeast is settling, the bagel hole gets SMALLER. As a class we
reasoned that the gas in the yeast releases pressure which expands the
bagel. But why is this behavior different from heating a metal
ring? This
question has never come up before, so I thought I'd ask the experts
(since I don't eat bagels much!).
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l