Report Question: What is that wire made of?

Most conductors we use for wires have very small resistances (< 1 $\Omega$). However, the long wire in the experiment had a larger than normal resistance. Let's figure out what it is made of.

Use this table of data to calculate the resistivity of the wire. Look up this value to determine what the wire is made of.

Some helpful math: $$\begin{equation} \frac{\Delta V}{\Delta R} = \frac{dV}{dR} = I \end{equation} $$ but $\rho = R \frac{A}{l}$ where $A$ is the cross sectional area of the wire and $l$ is the length. Thus, we can say: $$\begin{equation} \frac{dV}{dR} = \frac{dV}{d(x \rho / A)} = \frac{A}{\rho}\frac{dV}{dx} = I \end{equation} $$ The value of the current through the wire is $I$, and is something you measured earlier. The value of the $dV/dx$ is the slope of the line of your table of data. $A$ can be obtained from the diameter of the wire which is 750 μm. The only unknown is $\rho$, the resistivity.

Report Question: Why does this wire exist?

Normally, we want wire to be very conductive. Do some research and learn what applications exist for the type of wire in the long wire apparatus. Report on your findings.