Aim:

To find out how the length affects a wires resistance.

Nichrome-Area 0.164 x 10-6m2

-Resistivity 1.15 x 10-6 ohm metres

Resistivity is a property of all conductors. It tells us how conductive a material is, how many ohms within a metre. The higher the value, the more resistance a material has e.g. copper has a resistivity of 0.3 x 10-6 ohm metres therefore copper is a better conductor as it has less resistance within a metre compared to Nichrome. For any material, resistivity is linked to the resistance by the following equation.

R () = ℓ × L (m)

A (m²)

That means for any material of any length and area you can predict the resistance.

Planning and Method

Equipment

• Voltmeter - to measure the voltage in volts (V)
• Ammeter - to measure the current in amps (A)
• Nichrome wire on block - to measure...