An electical appliance is made up of different components.These components are connected to form an electric circuit.
A simple electric circuit is made up of 4 components.These are the:
-energy source
-switch
-wires
-output device
Switch:A switch controls the flow of the electric current in acircuit.The switch needs to be closed in order for the electric current to flow in the circuit.There are different types of switches.
Energy source:The battery is an energy source.There are 2 terminals-positive(+ve)and negative(-ve).There are chemicals inside the battery that react to produce an electric current when the positive and negative terminals are connected.
Output device:An output device is an electrical appliance that uses electricity to work.There are many different types of output devices,such as buzzers,small electric fans and light bulbs.
Wires:Wires are electrical conductors.They are used to connect one component of the circuit to another for electric current to flow.
A circuit diagram is a drawing that uses different symbols to represent an actual electric circuit.Each component of an electric circuit is represented by a symbol in acircuit diagram.
We can classify electric circuits based on the arrangement of the components in the circuit.Electric circuits are classified to:
-series circuit
-parallel circuit
Series circuit:A series circuit is a circuit that has components which are connected such as there is only one path for the electric current to flow through.
Advantage of series circuits:The advantage of using series circuits is that we can add more energy sources or batteries to the circuits to make the output of the applience more powerful.In the case of the torch below,this means that the bulb will light up brighter.
Disadvantage of series circuits:One of the disadvantage of using series circuits is that the output of the appliance will drop if we connect more output devices together in a series.This means that if a series circuits has 2 bulbs,the bulb will not light up as brightly as a series with only one bulb.Also,if one bulb is blown,the other bulbs will not light up.
Parallel circuit:A parallel circuit is a circuit that has parts which are connected such that there are more than one path for the elctric current to flow through.
Advantage of parallel circuits:The advantage of using parallel cirucits is that even if one bulb is blown,the other bulbs will still work.This is because in a parallel circuit,the electric current has more than one path to flow through.If one output device is broken,then no electric current will flow through that path.As the other paths are not affected,electric current can still flow through them.
Disadvantage of parallel circuit:The disadvantage of using parallel circuits is that wr cannot make the bulbs light up brighter by connecting more energy sources in parallel connection.
The brightness of a bulb in a circuit depends on the amount of electric current flowing through it.We can increase or decrease the amount of electric current flowing through the circuit byu changing the:
-numbetr of batteries
-nuimber of bubls
-arrangement of bulbs
Changing the nuimber of battteries:Connecting more bstteries to the series circuit makes the bulbs light up brighter.
Changing the number of bulbs:Connecting more bulbs to the series circuit,without changing the number of batteries,can make the bulbs dimmer.
Changing the arrangement of bulbs:Connecting more batteries to the series circuit makes the bulb light up brighter.
