The effect of temperature on conductivity and resistance
Our hypothesis has been proven to be true. As the temperature of the wire increased, he resistance of the wire increased and its conductivity fell.
The temperature of the wire increases due to its copper loss, which is calculated as I2x R., where I is the electric current flowing through the wire and R is its resistance. The higher the current in the wire or the higher the resistance, the higher the temperature of the wire. Therefore it is important to choose the correct wire size to minimize this unwanted loss and also prevent the risk of the wire burning.
What would happen if the science fair project were to be repeated using different wire sizes?
Modify the science project experiment, using aluminum wire instead.
Electrical resistance - http://en.wikipedia.org/wiki/Electrical_resistance
Electrical conductivity - http://en.wikipedia.org/wiki/Electrical_conductivity
Basic safety requirements