Electricity

Current, Potential Difference and PowerSign up

understand that electric current is the rate of flow of charged particles and be able to use the equation I = Q/t · understand how to use the equation V = W/Q · understand that resistance is defined by R = V/I and that Ohm's law is a special case when I is proportional to V for constant temperature

Resistance and ResistivitySign up

be able to use the equation R = rho l / A · CORE PRACTICAL 7: Determine the electrical resistivity of a material · be able to use I = nqvA to explain the large range of resistivities of different materials · understand how changes of resistance with temperature may be modelled in terms of lattice vibrations and number of conduction electrons and understand how to apply this model to metallic conductors and negative temperature coefficient thermistors · understand how changes of resistance with illumination may be modelled in terms of the number of conduction electrons and understand how to apply this model to LDRs.