The resistance of platinum wire at $0^{\circ}\,C$ is $2\,\Omega$ and $6.8\,\Omega$ at $80^{\circ} \,C$. The temperature coefficient of resistance of the wire is :
A$3 \times 10^{-1}{ }\;^{\circ}\,C ^{-1}$
B$3 \times 10^{-4}{ }\;^{\circ}C ^{-1}$
C$3 \times 10^{-3}{ }\;^{\circ}C ^{-1}$
D$3 \times 10^{-2}{ }\;^{\circ}C ^{-1}$
NEET 2023, Medium
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D$3 \times 10^{-2}{ }\;^{\circ}C ^{-1}$
d $R _{ T }= R _0\left[1+\alpha\left( T - T _0\right)\right]$
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