Q 12-03-014NEETNEET 2023Top questionEasy
The resistance of platinum wire at $0°$C is $2\ \Omega$ and $6.8\ \Omega$ at $80°$C. The temperature coefficient of resistance of the wire is :
Answer: (C) $3 \times 10^{-2}\ °\text{C}^{-1}$
$R_t = R_0(1 + \alpha t)$:
$$\alpha = \frac{R_t - R_0}{R_0\,t} = \frac{6.8 - 2}{2 \times 80} = \frac{4.8}{160} = 3 \times 10^{-2}\ °\text{C}^{-1}$$
Solution by Sreeraj P, M.Sc Physics