Resistance factors

Use this activity to reinforce your understanding of factors that affect resistance.

Follow the steps below to perform the practical activity of measuring the resistance values of various conductors.

1. Preparation

Download and print the Word document resistance factors (Word 82kb). This document provides instruction on the measurement of conductor types and a table to record the measured values.

Access the following equipment:

digital or analogue ohmmeter, or a multimeter
conductors of the following materials
- copper
- aluminium
- nichrome
- tungsten.

2. Measure resistances

With the conductors at room temperature, measure the resistance value of each conductor and record the value in the table provided.

Note: If you are having any difficulty or are unsure how to measure the resistance value of the conductors, see your trainer for assistance and advice.

Increase the temperature of each conductor and measure their resistance. Record the resistance value in the table provided.

Note: The conductor's temperature can be increased by warming in an oven or connecting the conductor, to a circuit allowing current to flow through the conductor.

3. Reflect on your results

Compare the resistance value of the conductor before and after warming. Determine if the conductor has a negative or positive temperature co-efficient. Record your determination in the table provided.

4. Submit the activity

Present your completed work to your trainer for feedback.

Return equipment and clean up your work area.

Note: The completed Word document can be saved as evidence of work completed.