Electricity and Magnetism

This lesson comprises eight (8) master classes focusing on:

• Electric charge
• Electric field and force
• Power, work and potential
• Ohm's law
• Electric circuits
• Magnetic field

Content:

PH11-11

How do charged objects interact with other charged objects and with neutral objects?

• Conduct investigations to describe and analyse qualitatively and quantitatively:
  • processes by which objects become electrically charged
  • the forces produced by other objects as a result of their interactions with charged objects
  • variables that affect electrostatic forces between those objects
• Using the electric field lines representation, model qualitatively the direction and strength of electric fields produced by:
  • simple point charges
  • pairs of charges
  • dipole
  • parallel charged plates 
• Apply the electric field model to account for and quantitatively analyse interactions between charged objects using:
  • \( \vec{F} =q \vec{E} \)
  • \( E=\frac{V}{d} \)
  • \( F=\frac{1}{4 \pi \varepsilon_0} \frac{q_1q_2}{r^2} \)
• Analyse the effects of a moving charge in an electric field, in order to relate potential energy, work and equipotential lines, by applying:
  • \( V=\bigtriangleup Uq \), where \( U \) is potential energy and \( q \) is the charge

How do the processes of the transfer and the transformation of energy occur in electric circuits?

• Investigate the flow of electric current in metals and apply models to represent current, including:
  • \( I=\frac{q}{t} \)
• Investigate quantitatively the current–voltage relationships in ohmic and non-ohmic resistors to explore the usefulness and limitations of Ohm’s Law using:
  • \( W=qV \)
  • \( V=IR \)
• 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 \( P=VI \) and \( E=Pt \) and variations that involve Ohm’s Law
• 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:
  • \( \sum I=0 \) (Kirchhoff’s current law – conservation of charge)
  • \( \sum V=0 \) (Kirchhoff’s voltage law – conservation of energy)
  • \( R_{series}=R_1+R_2+ \dots +R_n \)
  • \( \frac{1}{R_{parallel}}=\frac{1}{R_1}+ \frac{1}{R_2}+ \dots + \frac{1}{R_n} \)
• Investigate quantitatively the application of the law of conservation of energy to the heating effects of electric currents , including the application of \( P=VI \) and variations of this involving Ohm’s Law

How do magnetised and magnetic objects interact?

• Investigate and describe qualitatively the force produced between magnetised and magnetic materials in the context of ferromagnetic materials
• Use magnetic field lines to model qualitatively the direction and strength of magnetic fields produced by magnets, current-carrying wires and solenoids and relate these fields to their effect on magnetic materials that are placed within them
• Conduct investigations into and describe quantitatively the magnetic fields produced by wires and solenoids, including:
  • \( B=\frac{\mu_0 I}{2 \pi r} \)
  • \( B=\frac{\mu_0 NI}{L} \)
• Investigate and explain the process by which ferromagnetic materials become magnetised
• Apply models to represent qualitatively and describe quantitatively the features of magnetic fields

PH11-1

• Develop and evaluate inquiry questions and hypotheses to identify a concept that can be investigated scientifically, involving primary and secondary data
• Modify questions and hypotheses to reflect new evidence

PH11-5

• Derive trends, patterns and relationships in data and information
• Assess error, uncertainty and limitations in data
• Assess the relevance, accuracy, validity and reliability of primary and secondary data and suggest improvements to investigations

PH11-7

• Select and use suitable forms of digital, visual, written and/or oral forms of communication
• Select and apply appropriate scientific notations, nomenclature and scientific language to communicate in a variety of contexts
• Construct evidence-based arguments and engage in peer feedback to evaluate an argument or conclusion