Question

The temperature co-efficient of resistance of a wire is $0.0012{/}^{\circ }C$. Its resistance is $1\Omega$ at $300K$. At what temperature, its resistance will be $2\Omega$?

• A. $1133K$
• B. $854K$
• C. $1217K$
• D. $1154K$

Answer 1

Answer: (A)

$1133K$

Given : $\alpha =0.0012{/}^{o}C$ $R_{300}=1\Omega$ $T_1=300K$ $R^{\prime }=2\Omega$
Resistance at a temperature is given by $R^{\prime }=R_{300}(1+\alpha \Delta T)$
$\therefore$ $2=1(1+0.0012\times \Delta T)$
Or $\Delta T=T^{\prime }-300=833.33$
$⟹T^{\prime }=833+300=1133K$