1. Outline electrical conduction.
    • Conduction is due to the movement of the free electrons (transferring charge around a circuit);
    • metals are a good electrical conductor with large numbers of free electrons;
    • insulators are bad conductors with few/no free electrons;
  2. Define electromotive force (emf)
    The work done per unit charge in moving a quantity of charge completely around a circuit / the power delivered per unit current / work done per unit charge made available by the source;
  3. Describe how the resistance of a wire leads to a greater dissipation of power.
    • The resistance of a conductor increases with increasing temperature;
    • increased power (dissipation) leads to a higher temperature in the resistor / resistor heating up;
  4. Define ideal ammeter and ideal voltmeter
    • Ideal ammeter has zero resistance;
    • ideal voltmeter has infinite resistance;
  5. Define electronvolt
    • The energy gained by an electron when accelerated through an electric field with a potential difference of 1V;
    • 1.6x10^-19J;
  6. The definition of the ampere refers to
    The force between parallel current-carrying conductors;
  7. State Ohm's Law
    • The voltage is (directly) proportional to current / the ratio of potential difference to current is a constant called resistance / the resistance of a conductor is constant provided its temperature is
    • constant;
  8. Describe a potential divider.
    • Consists of two resistors in series or a potentiometer;
    • whereby the voltage traveling
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