Question

A silver wire has a resistance of 2.1 2 at 27.5 °C, and a resistance
of 2.7 12 at 100 °C. Determine the temperature coefficient of
resistivity of silver.​

Answer 1

Explanation:

$\Large{\pink{\underline{\underline{\sf{\purple{Solution:}}}}}}$

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$\hookrightarrow$ Temperature, $\sf T_1\:=\:27.5^{\circ}C$

$\hookrightarrow$ Resistance of the silver wire at $\sf T_1,\:R_1\:=\:2.1\Omega$

$\hookrightarrow$ Temperature, $\sf T_2\:=\:100^{\circ}C$

$\hookrightarrow$ Resistance of the silver wire at $\sf T_2$, $\sf R_2\:=\:2.7\Omega$

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Temperature co-efficient of silver = $\alpha$

It is related with temperature and resistance as,

 ‎ ‎ ‎ ‎ ‎ ‎ ‎

$\boxed{\sf{\orange{\alpha\:=\: \dfrac{R_2-R_1}{R_1(T_2-T_1)}}}}$

 ‎ ‎ ‎ ‎ ‎ ‎ ‎

$\leadsto$ $\sf \alpha\:=\: \dfrac{2.7-2.1}{2.1(100-27.5)}$

 ‎ ‎ ‎ ‎ ‎ ‎ ‎

$\leadsto$ $\sf \alpha\:=\:0.0039^{\circ}C^{-1}$

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$\longrightarrow$ Hence, the temperature co-efficient of silver is $\sf{\pink{0.0039^{\circ}C^{-1}}}$

Answer 2

Answer :

$0.0039 \: °C \: ^{ - 1}$

for explantion , please refer to the attachment above