The effect of temperature on conductivity and resistance
science fair projectThe materials required for this science fair project:
- 5 meters of varnish insulated copper wire with a diameter of 0.5mm (can be purchased from motor rewinding workshops)
- A PVC pipe about 300mm in length
- Three 1.5V batteries and the casing to hold the batteries
- 3 jumper wires with crocodile clip at both ends
- An ohm meter
- An ammeter that can measure currents up to 10A
- A paper cutter
- An infrared thermometer
- 1 roll of insulation tape
1. For this science fair project, the independent variable is the temperature of the copper wire. The dependent variable is the resistance of the wire. This is determined by measuring the current and resistance of the wire. The constants (control variables) are the room temperature, the applied voltage, the diameter of the wire and the length of the wire.
2. The wire with a length of 5 meters is wound around the PVC pipe. The ends of the wire are fixed to the pipe using the insulation tape. About 3 cm of insulation is removed from the wire tips using the paper knife. The resistance of the wire is measured using the ohm meter.
3. The 3 batteries are connected in series to produce 4.5V. The ammeter, batteries and wire wound around the pipe are connected as shown in figure 1. The connection is made using the jumper wires. This creates an electromagnetic field around the PVC pipe.
Basic safety requirements