Factors Affecting Resistance of Pencil Lead
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 include, pencil lead type (HB, 2B...), temperature, length and cross-sectional area.
Hypothesis:
The relationship between length and resistance should show an exponential relationship. The relationship between cross sectional area and resistance should be a power relationship. The type of lead and resistance will not show any linear relationship, but it is assumed that the more clay based leads 2h will have higher resistance than the more graphite based 6B. The temperature results will also be difficult to graph effectively due to very little change in the current and voltage.
Justification of Hypothesis:
As learnt in class, via earlier experiments, the longer the length of a resistor the lower the current as electrons have further to travel which intern gives a higher resistance. This has been proven by series circuits which is the method in which length will be tested. Area will be tested by using parallel circuits, doing so the cross-sectional area of the resistors is increased while the distance is kept the same. This allows the electrons to pass more freely increasing the current and reducing the resistance. The resistance of pencils of different lead types will be difficult to analyse as the grading of pencils does not incur
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 include, pencil lead type (HB, 2B...), temperature, length and cross-sectional area.
Hypothesis:
The relationship between length and resistance should show an exponential relationship. The relationship between cross sectional area and resistance should be a power relationship. The type of lead and resistance will not show any linear relationship, but it is assumed that the more clay based leads 2h will have higher resistance than the more graphite based 6B. The temperature results will also be difficult to graph effectively due to very little change in the current and voltage.
Justification of Hypothesis:
As learnt in class, via earlier experiments, the longer the length of a resistor the lower the current as electrons have further to travel which intern gives a higher resistance. This has been proven by series circuits which is the method in which length will be tested. Area will be tested by using parallel circuits, doing so the cross-sectional area of the resistors is increased while the distance is kept the same. This allows the electrons to pass more freely increasing the current and reducing the resistance. The resistance of pencils of different lead types will be difficult to analyse as the grading of pencils does not incur
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