(a) Describe, in a logical sequence, how you would set up a laboratory experiment to test whether a given metallic resistor follows Ohm’s law.
(b) State what observations you would record and how you would process them to reach a conclusion.
(c) Explain why, for a conductor that obeys Ohm’s law, the graph of potential difference plotted against current is a straight line passing through the origin.
(d) What physical quantity is represented by the slope of the graph in part (c) and how can its value be obtained from the graph?
(e) List two practical factors that can introduce a deviation from linearity even when the conductor itself is metallic.