solve

an aluminium wire and tungsten wire are of same length and

diameter at 0 C . at what temp .does aluminium wire have a same

resistance as tungsten at 20 C .

given

Ï_w = (5.6 ). 10 ^-8 Î© m

Ï_al = (2 . 8 )10 ^-8 Î© m

Î±_w = 4.5 .10^-3 / C

Î±_al = 4 .10^-3 / C

2 Answers

where

Ï-- resistivity

Î± -- temp .coefficient

use the direct formula na..

wats the problem??

Ï=Ï₀[1+Î±(T2-T1)]

and R is directly proportional to Ï

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