Transcript ammeters/voltmeters

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.