I haven't followed this thread that closely, but aren't we missing something
here?
The metal piece is expanding because the temperature of the material is
increasing. The bagel expands for much different reasons--probably more
similar to blowing up an inner-tube than heating a washer.
Rick (more into eating bagels than into bagel physics ;-)
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Richard W. Tarara
Professor of Physics
Saint Mary's College
Notre Dame, Indiana
rtarara@saintmarys.edu
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