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Def: Electricity is a form of energy

 

Electricity is the flow of charge.
All electrical devices in our homes change electricity from one form to another.
A battery provides the difference in electrical pressure necessary to drive electricity round a circuit.
Electric pressure is called potential difference and is measured in volts (V)
The volt is named after Alessandro Volta
Electricity will flow if there is potential difference and a complete circuit.
If energy is used in passing electricity through an object, that object is a resistor.
The unit of resistance is the ohm.
Electrical energy is changed to heat energy in a resistor

 

Def: An electrical current is the flow of electrical charge.

 

Electric current is measured in amperes (amps).
To measure electric current we use an ammeter.
Andre Ampere was a French physicist who demonstrated that electrical currents produce magnetic fields.
Series Circuits: Bulbs connected in series are connected one after another.
Parallel circuits: Bulbs connected in parallel are side by side in a circuit. (e.g. house lights)
Current flows from + to -.
The long line = positive
The short line = negative
Ammeter always connected into a circuit in series.
A voltmeter is always connected into a circuit in parallel.