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Firstly I am sorry if this is in the wrong place but I was unsure exactly where it fits in as it involves physics, integrated equations, and computer programming.

I am trying to write an emulator for a machine which is running 256 filament lamps in a 16*16 matrix.

I want to simulate the brightness levels in near real time.

I am working from this pdf file http://physik.uibk.ac.at/04-05/erde/spezial/aufgaben/Gluehbirne.pdf

My question relates specifically to equation at the end which gives the Adiabatic SwitchingTime (8).

I am trying to replicate the function in computer code using the example given in the pdf as inputs, in the hope that I can get the outputs to match the example to ensure the maths is correct. Then I can substitute the values of the bulbs I am using and use that for calculating the current temperature of the filament, which in turn can be converted to a brightness level to be displayed on the screen.

Using the inputs given in the example I can correctly calculate the resistance, maximum inrush current, & steady state temperature. But when using the final function to calculate the switching time, the value I get back is 0.0142 and according to the pdf should be 0.06.

I've been through the code and checked that I am doing things in the correct order (BODMAS) and that seems to be correct. However because I am not a mathematician, or a physicist, I am not even sure whether the equation is correct. There could be a glaring error and I would never know because I am not experienced in working with this level of maths. This is not homework, If I had a physics or maths professor, I would ask them for help.

So my opening questions are..

1) Does the equation (8) in the pdf look correct?

2) If I post C++ code here will it be of any use?

3) Please can anybody help?

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# Adiabatic switching time of a filament lamp

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