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) ...
Resistivity Resistance, 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 resista...
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...
Coulomb's Law Any charged particle generates an electric field This field exerts a force on any other charged particle within range The electrostatic force between two charges is defined by Coulomb...
Electric Fields An electric field is a region of space in which an electric charge “feels” a force It is a vector field The direction of the electric field is the same as the direction of the elect...
Potential Difference Potential difference is a measure of the electrical potential energy transferred from an electron as it moves between two points in a conductor Potential difference is work don...
