A wire has a resistance of 7.5 Ohms at 22°C and 15.7 Ohm at 175°C. Determine the temperature coefficient of resistance of the material.
Answer & explanation
Correct answer: option 1
Temperature coefficient : α = \(\frac{R - R_{o}}{θR_{o}}\)
R = 15.7 Ohms ; Ro = 7.5 Ohms ; θ = (175 - 22) °C-1 = 153 °C-1
α = 7.1 x 10-3 °C-1