Question

A metal wire has a resistance of 25.00 W under room temperature conditions of 25°C. When the wire is heated to 85°C the resistance increases by 0.75 W. What is the temperature coefficient of resistivity of this metal?

Answer 1

To determine the temperature coefficient of resistivity (α) for the given metal wire, we can use the formula:

α = (ΔR/R₀) / ΔT

Where: α is the temperature coefficient of resistivity, ΔR is the change in resistance (0.75 Ω in this case), R₀ is the initial resistance (25.00 Ω), ΔT is the change in temperature (85°C - 25°C = 60°C).

Plugging in the values into the formula:

α = (0.75 Ω / 25.00 Ω) / 60°C

Simplifying:

α = 0.03 / 60°C

Dividing the numerator by the denominator:

α = 0.0005 1/°C

Therefore, the temperature coefficient of resistivity for this metal wire is 0.0005 1/°C.