IB HL Physics 2025-32 - B5. Current and circuits

B5. Current and circuits

How do charge particles flow through materials?

How are the electrical properties of materials quantified?

What are the consequences of resistance in conductors?

In what ways can an electrical circuit be described as a system like the Earth’s atmosphere or a heat engine?
How are the fields in other areas of physics similar to and different from each other?
How can the heating of an electrical resistor be explained using other areas of physics?
What are the advantages of cells as a source of electrical energy?
How does a particle model allow electrical resistance to be explained? (NOS)
What are the parallels in the models for thermal and electrical conductivity? (NOS)

that cells provide a source of emf
chemical cells and solar cells as the energy source in circuits
that circuit diagrams represent the arrangement of components in a circuit
direct current (dc) I as a flow of charge carriers (I=ΔQ/ΔT)
that the electric potential difference V is the work done per unit charge on moving a positive charge between two points along the path of the current
the properties of electrical conductors and insulators in terms of mobility of charge carriers
electric resistance and its origin
electrical resistance R (R=V/I)
resistivity (ρ =RA/L)
Ohm’s law
the ohmic and non-ohmic behaviour of electrical conductors, including the heating effect of resistors
electrical power P dissipated by a resistor as given by P = IV
the combinations of resistors in series and parallel
that electric cells are characterized by their emf ε and internal resistance r as given by ε = I(R + r)
that resistors can have variable resistance.