If the resistance of copper wire is 50 ohm at 20°C, what is the resistance at 100°C?
To find the resistance at 100°C, we can use the temperature coefficient of resistance for copper, which is approximately 0.00427 per degree Celsius.
First, we need to calculate the change in temperature: ΔT = T₂ - T₁ = 100°C - 20°C = 80°C.
Next, we can use the equation: R₂ = R₁ * (1 + α * ΔT), where R₂ is the resistance at the new temperature, R₁ is the resistance at the initial temperature, α is the temperature coefficient of resistance, and ΔT is the change in temperature.
Substituting the values, we have:
R₂ = 50 ohm * (1 + 0.00427/°C * 80°C)
= 50 ohm * (1 + 0.3424)
= 50 ohm * 1.3424
= 67.12 ohm.
Therefore, the resistance of the copper wire at 100°C is approximately 67.12 ohms.