A certain lightbulb has a tungsten filament with a resistance of 21.0 when cold and 135 when hot. Assume that Equation 17.8 can be used over the large temperature range involved here, and find the temperature of the filament when it is hot. Assume an initial temperature of 20°C.
2007-07-26 13:28:24 · 4 answers · asked by makk 3 in Science & Mathematics ➔ Physics
i dont know, i was not given the equation , just the question
2007-07-26 14:40:42 · update #1
Ignore that equation which is not known but we know R2 = R1 x [1 + α (T2 –T1)]
Given R2 = 135, R1 = 21 and T1 = 20° C.
1 + α (T2 –T1) = 6.43
α (T2 –T1) = 5.43
(T2 –T1) = 5.43 / 0.004403 using α = 0.004403
(T2 –T1) = 1233.25 ° C
T2 = 1213.25° C
2007-07-26 21:41:42 · answer #1 · answered by Pearlsawme 7 · 0⤊ 0⤋
I'll bet equation 17.8 is in chapter 17. I just checked your recent questions. Sounds like you're completely lost with all your homework problems after a grand and noble struggle. If you get any more desperate, you'll just have to read chapter 17. Gads!
2007-07-26 23:16:27 · answer #2 · answered by Dr. R 7 · 0⤊ 1⤋
I believe you are looking for the restistor tempature coeffiecient. You will find it in the first link below. Now all you need is alpha the constant for tungsten you will find it in the second link.
2007-07-26 21:45:53 · answer #3 · answered by alints_2000 4 · 0⤊ 0⤋
what is equation 17.8?
2007-07-26 21:35:04 · answer #4 · answered by throbbin 3 · 0⤊ 0⤋