-- Core –

✔

State that there are positive and negative charges.

State that positive charges repel other positive charges, negative charges repel other negative charges, but positive charges attract negative charges.

Describe simple experiments to show the production of electrostatic charges by friction and to show the detection of electrostatic charges.

Explain that charging of solids by friction involves only a transfer of negative charge (electrons).

Describe an experiment to distinguish between electrical conductors and insulators.

Recall and use a simple electron model to explain the difference between electrical conductors and insulators and give typical examples.

Know that electric current is related to the flow of charge.

Describe the use of ammeters (analogue and digital) with different ranges.

Describe electrical conduction in metals in terms of the movement of free electrons.

Know the difference between direct current (d.c.) and alternating current (a.c.).

Define electromotive force (e.m.f.) as the electrical work done by a source in moving a unit charge around a complete circuit.

Know that e.m.f. is measured in volts (V).

Define potential difference (p.d.) as the work done by a unit charge passing through a component.

Know that the p.d. between two points is measured in volts (V).

Describe the use of voltmeters (analogue and digital) with different ranges.

Recall and use the equation for resistance: R = V/I

Describe an experiment to determine resistance using a voltmeter and an ammeter and do the appropriate calculations.

State, qualitatively, the relationship of the resistance of a metallic wire to its length and to its cross-sectional area.

Understand that electric circuits transfer energy from a source of electrical energy, such as an electrical cell or mains supply, to the circuit components and then into the surroundings.

Recall and use the equation for electrical power: P = IV

Recall and use the equation for electrical energy: E = IVt

Define the kilowatt-hour (kW h) and calculate the cost of using electrical appliances where the energy unit is the kW h

-- Extended –

✔

State that charge is measured in coulombs

Describe an electric field as a region in which an electric charge experiences a force.

State that the direction of an electric field at a point is the direction of the force on a positive charge at that point.

Describe simple electric field patterns, including the direction of the field:

a)around a point charge

b)around a charged conducting sphere

c)between two oppositely charged parallel conducting plates (end effects will not be examined).

Define electric current as the charge passing a point per unit time; recall and use the equation I = Q/t.

State that conventional current is from positive to negative and that the flow of free electrons is from negative to positive.

Recall and use the equation for e.m.f.: E = W/Q.

Recall and use the equation for p.d.: V = W/Q.

Sketch and explain the current–voltage graphs for a resistor of constant resistance, a filament lamp and a diode.

Recall and use the following relationship for a metallic electrical conductor:

a)resistance is directly proportional to length

b)resistance is inversely proportional to cross-sectional area