4. Discussion

Key findings & Analysis of results

The voltage produced increased when we increased the number of junctions
from 1 to 2 but decreased sharply when we added another junction to our set-up.
The voltage increased slightly when we added the fourth junction to our set-up,
then decreased to about the same amount of voltage produced when there were
3 junctions.

Explanation of key findings  

The reason the voltage produced increased from 1 junction to 2 junctions is that
the experiment was carried out properly and the voltage increase was normal. The
reason the voltage produced decreased sharply is likely due to the fact that the experiment was not carried out that well which resulted in the
voltage produced is decreasing. The rest of the experiment was carried out in
the same way which was the reason the voltage produced remained the
same.

Evaluation of Hypothesis

The hypothesis may have been correct. The experiment may have been conducted
incorrectly, causing our result to differ from our prediction.

Limitations and Areas for improvement

1. The temperatures of the hot and cold junctions could not be kept at a constant temperature, as we were not able to regulate the temperature of the water bath and the ice. This was caused as we did not have any equipment that allowed us to regulate the temperature of the water and the ice. Instead, we had to use a bunsen burner, which is not able to regulate its temperature, and we did not have anything that would have allowed us to keep the temperature of the ice constant. Because of this, We were had to rely on an infrared thermometer to measure the temperatures of the water bath and the ice, causing the difference in temperature to be different for each experiment.

2. We were not able to solder the junctions properly. While soldering, the solder would not stay on the wire, would instead roll off it. As such we had to melt the solder first before placing the wire into the melted solder. This may have caused the voltage produced to change, as the soldering may have interfered with the experiment.

3. The experiment set up took up a lot of space and it was also quite close together which caused the bunsen burner to heat up and melt the ice. This may have caused the temperature difference to be lower which caused it to have a lower voltage produced