(adsbygoogle = window.adsbygoogle || []).push({}); 1. A standard 100 W (120 V) lightbulb contains a 8.50 cm-long tungsten filament. The high-temperature resistivity of tungsten is 9.0*10^{ - 7} ohm*m. What is the diameter of the filament?

2. p= resistivity, E = V/L, I = AV/pL, R = pL/A...

3. I know that I'm going to solve for A = pi*r^{2}, find r and multiply by 2 to get the diameter, but I just don't see how to do it with what I'm given. For example, I could do pi*r^{2}= IpL/V but I don't know I, or A = pL/R but I don't know R....

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# Homework Help: Diameter of wire from voltage, length, resistivity

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