Practice Notes

• Using the electric field lines representation, model qualitatively the direction and strength of electric fields produced by:


  1. Simple point charges

  2. Pairs of charges

  3. Dipoles

  4. Parallel charged plates
• Apply the electric field model to account for and quantitatively analyse interactions between charged objects using:


  1. F = qE

  2. E = U/q
• Analyse the effects of a moving charge in an electric field, in order to relate potential energy, work and equipotential lines, by applying:


  V = U/q
• Investigate the flow of electric current in metals and apply models to represent current, including:

  I = q/t
• Investigate quantitatively the current-voltage relationships in ohmic and non-ohmic resistors to explore the usefulness and limitations of Ohm's Law using:

  1. W = qV

  2. V = IR
• Investigate quantitatively and analyse the rate of conversion of electrical energy in components of electric circuits, including the production of heat and light, by applying:

  1. P = VI

  2. E = Pt
• Investigate qualitatively and quantitatively series and parallel circuits to relate the flow of current through the individual components, the potential differences across those components and the rate of energy conversion by the components to the laws of conservation of charge and energy, by deriving the following relationships:


  1. ΣI = 0 (Kirchhoff's current law - conservation of charge)

  2. ΣV = 0 (Kirchhoff's voltage law - conservation of energy)

  3. 1/Rseries = 1/R1 + 1/R2 + ... + 1/Rn

  4. 1/Rparallel = 1/R1 + 1/R2 + ... + 1/Rn
• Investigate quantitatively the application of the law of conservation of energy to the heating effects of electric currents, including the application of:

  P = VI
• Conduct investigations into and describe quantitatively the magnetic fields produced by wires and solenoids, including:

  1. B = μ0NI/2πr

  2. B = μ0NI/L