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...
Kirchhoff's Circuit Laws Kirchhoff's First Law Kirchhoff’s first law states that: The sum of the currents entering a junction always equals the sum of the currents out of the junction A junction is...
Resistance As electrons move through the metal wire of a circuit (or any other component), they transfer some of their electrical potential energy to the positive ions of the metal Free electrons c...
Circuit Diagrams The diagram below shows the various circuit symbols that could be used in circuit diagrams Common circuit symbols Functions of Most Common Components Switch: it turns the circuit o...
