B5 practical: Factors affecting R (pencil)
Pencil lead is made out of graphite which conducts electricity so a line drawn on a piece of paper has electrical resistance that can be measured using a multimeter. In this practical the resistance of different lines will be measured to see how the resistance of a line is related to its length and thickness. The resistance of a conductor is given by the equation Where ρ = resistivityL = lengthA = Cross sectional...