Dewars (set of 4 in rack) and Computer
Data on the Computer from Demo
Dewars (set of 4 in rack), Thermometers (4),

 

Code Number: 4B50.10

Demo Title: Thermal Conductivity Demo - 4 Thermos Bottles

Condition: Good

Principle: Thermal Conductivity

Area of Study: Thermodynamics

Equipment: 

Dewars (set of 4 in rack), Thermometers (4), and Computer.

Procedure:

Information about the Dewar demo is attached to the rack stand.  Basically there is a silvered and evacuated, a silvered and unevacuated, unsilvered and evacuated, and unsilvered and unevacuated dewars.  This allows for different amounts of heat loss.  Boiling water is added just before this is taken into the classroom and even then the starting temperatures will be in the 88 to 92 degree centigrade range.  Temperature decline vs. time is then recorded for each flask.

References:

  • Thomas B. Greenslade Jr., "Apparatus Named After Our Academic Ancestors - VI", TPT, Vol. 62, #4, April 2024, p. 259.
  • Rosaria Conti, Aurelio Agliolo Gallitto, Emilio Fiordilino, "Measurement of the Convective Heat-Transfer Coefficient", TPT, Vol. 52, #2, Feb. 2014, p. 109.
  • Paul Hewitt,"Figuring Physics: Steep Well", TPT, Vol. 50, #1, Jan. 2012, p. 8.
  • Roland Berger, "Some Interesting Thermodynamics of the Thermos Flask", TPT, Vol. 45, #5, May 2007, p. 270.
  • Peter Drago, "Teaching with Spreadsheets: An Example from Heat Transfer", TPT, Vol. 31, #5, May 1993, p. 316.
  • Michael A. Karls and James E. Scherschel, "Modeling Heat Flow in a Thermos", AJP, Vol. 71, #7, July 2003, p. 678.
  • Feier and Anderson, "Hd- 3", A Demonstration Handbook for Physics.