Physic Rate of Reaction

Preliminary Work

Before I begin this investigation properly, I will need to decide which type of wire to use. To discover this I had to do the following preliminary work.

I tested three types of wire for this preliminary work; they were constantan, copper and nichrome, to see which one had the best range of resistance. We did it with a light bulb and we found out that the constantan wire had the best range of brightness in the bulb. We then checked again with the constantan wire to make sure it was correct. We did this by moving the crocodile clips 10cm along the wire every time. This gave us the theory that the longer the wire the greater the resistance. We also tested the width of the wire after discovering which wire gave us the best results. When testing nichrome and copper they didn't give us such a range of results. Copper is a good conductor of electricity so we thought it wouldn't have as sturdy resistance as the others.

Safety

To make sure we were safe we chose to put heat mats under the wire so that it didn't burn the surface. Also we were not allowed to touch the wire whilst the power pack was on so we didn't burn ourselves. We never left the equipment unattended whilst in use and before moving the crocodile clips we switched off the power pack. Finally we made sure the volts were not higher than 4 volts as we didn't want to burn the wires