[net.physics] Temperature Coeffecient of Resistance

lew (01/22/83)

When I was a TA for freshman physics at Lehigh U., I worked out
the I-V characteristic for a light bulb based on the assumptions
R=T and P = I*V = T^4.  This gives I*V = ((V/I)^4 or I^5 = V^3.
It was a student assignment to measure this characteristic, so I
had lots of data available. I plotted log I vs. log V and found
the slope to be .586, which compares favorably to the predicted
value of .6 -- and the line was nice and straight too. This
indirectly verifies the validity of the R=T relation over a
temperature range of (T1/T0) =  2.5 , corresponding to a voltage
range of from 1 to 10 volts (use V^2=T^5).

Lew Mammel, Jr. ihuxr!lew