Robert Cinca - Physics
of 4.3 13 , so it could have played an important part, especially considering the large
change in temperature (from room temperature to around 2800K). The third possible
reason is that the emissivity of tungsten could have changed due to the changes in
temperature: this may have resulted in a smaller net energy flow into the filament
bulb and thus a longer surge current time.
To further improve my model, I would include a changing emissivity of tungsten
value with temperature, a volume expansion coefficient and the idea of self-
inductance.
13
“Coefficients of Linear Thermal Expansion”, The Engineering Toolbox [Online][Date Accessed
18/07/13] URL: http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html (The
Engineering Toolbox)
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