Final answer:
To find the maximum percent decrease in the resistance of a constantan wire, you can use the formula ΔRmax/Rinitial = - α(Tfinal - Tinitial), where α is the temperature coefficient of resistivity. By plugging in the values given in the question, you can calculate the maximum percent decrease in resistance.
Step-by-step explanation:
To find the maximum percent decrease in the resistance of a constantan wire, we need to consider the temperature coefficient of resistivity. The temperature coefficient of resistivity is a constant that represents how the resistance of a material changes with temperature. Assuming a constant temperature coefficient of resistivity, the maximum percent decrease in resistance can be calculated using the formula:
ΔRmax/Rinitial = - α(Tfinal - Tinitial)
Where ΔRmax is the maximum decrease in resistance, Rinitial is the initial resistance, α is the temperature coefficient of resistivity, Tfinal is the final temperature, and Tinitial is the initial temperature. Since the problem states that the temperature coefficient of resistivity is constant, we can assume α is constant. From the given temperature change, we subtract the final temperature (100.0 °C) from the initial temperature (20.0 °C) to find the temperature change. Plugging in the values, we can solve for ΔRmax/Rinitial to find the maximum percent decrease in resistance.