Determination of the Resistivity of Constantan Wire

Physics Coursework

Determination of the Resistivity of Constantan Wire

To calculate the resistivity of constantan wire, or any other type of wire, the resistance has to be calculated, as well as the cross sectional area and also the length.



Resistivity of constantan wire can be determined by using the equation:
ρ = RA/L

ρ = resistivity
R = resistance of wire in Ohms (Ω)
Resistance is calculated by using R = V/I = Voltage/Current
Voltage is measured in Volts, and Current is measured in Amperes
A = cross sectional area of the wire (metres square)
Cross sectional area can be calculated by A = πd2/4
d = diameter
L = length of constantan wire (metres)




Physics Coursework

List of apparatus:
• Power Pack Supply
• Variable Resistor
• Ammeter (0 – 1 Amperes)
• Voltmeter (0 – 6 Volts)
• Constantan Wire
• 1m Ruler
• ...