Terminal Potential Difference Defining Potential Difference A cell makes one end of the circuit positive and the other negative. This sets up a potential difference V across the circuit The potenti...
Investigating Electric Cells Zinc-carbon cells Zinc-carbon cells are the most common type of primary cells, consisting of a zinc casing which acts as the negative electrode a paste of ammonium chlo...
Primary & Secondary Cells Simple Cells A simple cell is a source of electrical energy The simplest design consists of two electrodes made from metals of different reactivity immersed in an elec...
Potential Divider Circuits When two resistors are connected in series, through Kirchhoff’s Second Law, the potential difference across the power source is divided between them Potential dividers ar...
Heating Effect of Current When electricity passes through a component, such as a resistor, some of the electrical energy is turned into heat, therefore, increasing its temperature The heat that is ...
Series & Parallel Circuits The following statements for series and parallel circuits are a consequence of Kirchhoff's first and second law In a series circuit: The current is the same at any po...
Investigating Resistivity Aims of the Experiment The aim of the experiment is to determine the resistivity of a 2 metre constantan wire Variables: Independent variable = Length, L, of the wire (m) ...
ResistivityResistance, Length and Cross-Sectional Area The resistance of a sample depends on: The material it is made of The length of the sample The cross-sectional area of the sample The resistan...
Ohm's Law Ohm's law states that: For a conductor at a constant temperature, the current through it is proportional to the potential difference across it An electrical component obeys Ohm’s law if i...
