Question

The temperature coefficient of resistivity for copper is 0.0068 (C°)-1. If a copper wire has a resistance of 104 Ω at 20°C, what is its resistance 80°C?

Answer 1

Answer:

R₈₀ = 146.43 Ω

Explanation:

The resistance of a resistor depends upon many factors. One of the main factors of the change in resistance of a resistor is the change in temperature. The formula for the resistance at a temperature other than 20°C is given as follows:

R₈₀ = R₀(1 + αΔT)

where,

R₈₀ = Resistance of wire at 80°C = ?

R₀ = Resistance of wire at 20° C = 104 Ω

α = Temperature coefficient of resistance for copper = 0.0068 °C⁻¹

ΔT = T₂ - T₁ = 80°C - 20°C = 60°C

Therefore,

R₈₀ = (104 Ω)[1 + (0.0068°C⁻¹)(60°C)]

R₈₀ = 146.43 Ω