Physics - Currents, Circuits, & Electric fields

potential difference

a measure of the electrical potential energy transferred to or from an electron when it is moving between two points in a circuit

effects of electric current

• heating effect → energy transferred to a resistor as internal energy

• magnetic effect

• chemical effect

ohm’s law

the potential difference across a metallic conductor is directly proportional to the current in the conductor, providing that the physical conditions of the conductor don't change

the resistance of a conductor is

• proportional to its length

• inversely proportional to its cross-sectional area

thermistor

resistance varies with temperature; temp increases, resistance falls

LDR

resistance varies with light intesnsity; light intensity increases, resistance falls

emf

the terminal potential difference when no current is supplied