What we will do today: State the function of a supply voltage (from any power source). Carry out experiments to correctly connect both voltmeters and ammeters.

What does voltage mean? The voltage is a measure of the energy available to move charges around a circuit. It has the unit volt (V). Further explanation: A supply voltage of 1 volt means that 1 joule of energy is supplied to each coulomb of charge.

Supply Voltage & Current If the supply voltage in a circuit increases then the current also increases. E.g. If the supply voltage to a bulb increases the bulb will get brighter. This is because the flow of charges is increased.

Position of Ammeter (don’t copy) If we have a circuit with a battery and bulb, how can we determine which way the Ammeter should be placed? How should we set up our circuit?

Measuring current When measuring current, the ammeter must be set up in series. E.g. beside the component.

Position of Voltmeter (don’t copy) If we have a circuit with a battery and bulb, how can we determine which way the voltmeter should be placed? How should we set up our circuit?

Measuring voltage When measuring voltage, the voltmeter must be set up “parallel”. E.g. above or below the component.

2006 Qu: 8

What have we learned today? Voltage of a supply is a measure of the energy given to the charges in the circuit. If the supply voltage is increased so is the current. A voltmeter must be set up in parallel in a circuit. An ammeter must be set up in series in a circuit.