Factors Affecting Resistance of Pencil Lead

Abstract:
The investigation involved testing the factors of pencil lead length, cross-sectional area, temperature and lead type to find out how they affected pencil resistance. The hypothesis was proven as the length (series circuit) graph was exponential and the area (parallel circuit) graph was that of a power function. Higher clay based pencils (2H) had higher resistance to that of higher graphite based pencils (6B), and temperature did not greatly affect the resistance. The reasons as to why diamond does not conduct electricity were also found.

Aim:
To investigate the effect that different factors have on pencil lead (graphite) resistance. The factors tested …show more content…
The results that were found resembled that of which were hypothesised. The results show an exponential relationship between length and resistance this point was hypothesised and proven. The relationship between cross-sectional area and was also proven to be that of a power relationship. The temperature results, or time results, would have been difficult to graph due to the many factors and the little change in voltage and current. The type of lead hypothesis was also proved as can easily be seen in both the table and the graph; the more clay based (2H) pencils had a higher resistance than that of the more graphite based pencils (6B).
The experiments were also made in a way that factors and any experimental error was reduced. As with the length of pencils, each pencil was sharpened on both ends until it reached 17.5cm each pencil was measured carefully against a