Question

How do
you verify that resistance of a conductor is
inversely propostional to the area of cross section of the
conductor for constant length and temperatae ?​

Answer 1

Aim:

To verify that the resistance of a conductor is inversely proportional to the area of cross section of the conductor for constant length and temperature.

Material Required:

A plug key, a battery, an ammeter, a wire, iron spokes with different cross section areas.

Procedure:

1. Collect iron spokes of different cross section areas; with same length.
2. Make a circuit leaving a gap between A and B with a battery, ammeter and plug key.
3. Connect one of the iron spoke say of diameter 1 mm between A and B.
4. Use the ammeter to measure the value of current with different iron spokes of different cross-section areas.
5. Record your observations.

Observation:

• You will observe that the current increases with the increase in cross section area of iron spokes.
• Thus, the resistance of the each spoke decreases with the increase in the area of cross-section.

Conclusion:

The resistance of a conductor is inversely proportional to the area of cross section. $R$ ∝ $\frac{1}{A}$

Hope you got that.

Thank You.