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

A 2.5 cm length of tungsten filament in a

small lightbulb has a resistance of 0.041

.

Find its diameter. (The resistivity is

5.6 × 10−8

· m).

Answer in units of mm.

2. Relevant equations

R=p(L/pi*r^2)

3. The attempt at a solution

i have reworked the equation to the square root of pL/R*pi equals r and then multiplied that answer by 2 which nds u being 2.0856e-4 but it is not right??

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# Homework Help: Electric Resistance

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