1) Collect different metal rods of the same length and same cross sectional area like copper, aluminium, iron etc.
2) Make circuit leaving gap between P and Q as shown in figure.
3) Connect one of the metal rods between P and Q
: and switch on the circuit.
4) Measure the current using an ammeter and note the value.
5) Repeat this with other metal rods and measure electric current in each case.
6) The values of current are different for different metal rods for a constant potential difference,
7) From this we conclude that the resistance of a conductor depends on the material of the conductor.