(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I'm doing a lab where I'm trying to find the emissivity of a tungsten filament. I measured voltage and current of a bulb with a tungsten filament and found the power. Then I plotted Power vs Temperature^4 and used the slope along with surface area and Boltzman's constant to find the emissivity. But I am expected to plot ln(P) vs ln(T) and find the emissivity and I can't quite figure out how to do that.

2. Relevant equations

I plotted it bas on this equation

ln(P) = ln(a) +n ln(T)

which was derived from the equation

P = aT^n

3. The attempt at a solution

I'm lost for this part. I've found everything else I'm supposed to except for this. i found n to be close enough to 4 and can find a from the intercept, but I'm not really sure what a stands for. Is that the emissivity?

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# Homework Help: How to find emissivity of tungsten from ln graph?

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