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PRACTICE / Temperature dependence of resistance

Use the stated reference resistance

A wire has resistance 10.0 Ω at 20°C and 13.0 Ω at 80°C. Assume R(T) = R20[1 + α20(T − 20°C)].

Find α20.

Organize the givens & assumptions
  • R20 = 10.0 Ω
  • R80 = 13.0 Ω
  • Temperature difference = 60 K

The linear model is valid over this range; geometry changes are included in the measured resistance model.

  1. A5.0×10−3 K−15.0\times10^{-3}\ \mathrm{K^{-1}}
  2. B1260 K−1\frac1{260}\ \mathrm{K^{-1}}
  3. C3.75×10−3 K−13.75\times10^{-3}\ \mathrm{K^{-1}}
  4. D0.30 K−10.30\ \mathrm{K^{-1}}

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