In a circuit there are electrical components . This is a device such in an
electric circuit such as: a battery, a switch or lamp etc.These connect
together in two ways: series or in parallel.
When batteries, cells and lights are connected in a sequenceit is called a series.
The same value of current, this is a moving electrical charge which flows
through each component,connected in a series.
Two lamps connected in series
The circuit illustrates a circuit with two lamps connected in series. If one of
the lamp breakdowns, the other lamp will not light because it is in a series.
Here we have, two lamps connected in series with an open switch and a cell:
Series circuits are helpful to identify when one of the components has
broken-down. For example, a fuse, which is a device which controls the
overload of the current to keep it safe, must be connected in series in
order for it to work. If Christmas tree lights all go out when one bulb
breaks, they are connected in series.
The sum of all the potential differences across the components in a series
circuit is equal to the total potential difference across the power supply.
Parallel connections are when components such as lights that are connected
on separate loops.Here, the current is divided between each component
connected in parallel.If one lamp breaks, the other lamp will still light.
Two lamps connected in parallel with an open switch and a cell
In our homes, the lights are connected in parallel and ensures each bulb
receives the full voltage. If one bulb breaks the others remain on.
In a parallel circuit the current supply of electricity is more than the current in
each branch. Note, ehe sum of all the current in every of the branches
equals to the current from the electrical supply.
Electricity Supply = branch 1 + branch 2 + branch 3
If the current constantly changes direction it is called alternating current, or
AC. Mains electricity is an AC supply. The UK mains supply is about 230 V.
It has a frequency of 50 Hz, which means that it changes direction and back
again 50 times a second. The diagram shows an oscilloscope screen
displaying the signal from an AC supply.
Oscilloscope trace illustrating alternating current
DC is when a current flows in only one direction. Examples of DC electricity
are batteries and solar cells supply DC electricity. A battery typically supplies
1.5 V. The illustration shows an oscilloscope screen. It is displaying the
signal from a DC supply.