What is the relationship between length of a conductor and its resistance ? Write the experimental procedure to verify that relationship.

Explanation

1. Collect manganin wires of different lengths with the same cross-sectional areas.
2. Make a circuit as shown in the figure.
3. Connect one of the manganin wires between P and Q.
4. Measure the value of the current the ameter connected to the circut and note it in your notebook.
5. Repeat this for other length of the wires. Note the corresponding values of currents in your notebook as shown below.

6. We observe that current decreases as the length of the wire increases.
7. We know that resistance increases as current decreases.
8. Hence the resistance of manganin wire increases as its length increases:
9. We conclude that the resistance of a conductor is directly proportional to its length for a constant potential difference and constat cross-sestional area.
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