There once was a time when the ability to wire a 3-pin plug was an essential skill - but not any more. For reasons of safety, many devices are now fitted with molded plugs that cannot be opened or removed. Nevertheless, the exam board still expects you to be able to identify the essential features … Continue reading Correct wiring of a 3-pin plug
DC and AC Electricity Pt1: Electron Movement
One of the most famous technological "wars" was the battle that raged almost 150 years ago between Thomas Edison's DC electricity and Nikola Tesla's AC electricity. For our purposes, we will put aside the stories of the two men (Edison was an inventor and businessman whereas Tesla was a scientist and idealist) and focus on … Continue reading DC and AC Electricity Pt1: Electron Movement
Electrical Circuits: mini-test
It is really important that you check your understanding as you work through a topic. With that in mind, I have created a short online test that you can use to check your recall and understanding of some of the basic knowledge required for the Electricity module. You can access the test, which is hosted … Continue reading Electrical Circuits: mini-test
Current and Voltage rules
There is a clear pattern to the measurements of current and potential difference (voltage) in electrical circuits - which, for us, means series and parallel circuits. These two patterns were identified by Gustav Kirchhoff and are therefore known as Kirchhoff's Laws. Kirchhoff's current law states that the sum of the currents flowing into a junction … Continue reading Current and Voltage rules
Series and Parallel Circuits
Electric circuits are all about energy transfers: they allow the energy in the original source to be transferred via electricity into some other form. In the classic torch-bulb circuit, for example, chemical energy (in the cells) is converted into electrical energy, which is then converted into light (and heat, for old-fashioned bulbs). The amount of … Continue reading Series and Parallel Circuits
What is Static Electricity?
When work is done on an object, by moving a force through a distance, the object gains energy. As a result, the object might get hotter (gain thermal energy) or accelerate (gain kinetic energy) or be lifted upwards (gain gravitational energy). There is also another possibility; the object could gain electrical energy in the form … Continue reading What is Static Electricity?
Voltage and Current
When you first started learning about circuits, either in primary school or in Y7, you should have been told about voltage and current. These two measurements were probably presented as separate ideas but in fact they both relate to one thing; electrical charge. Voltage relates to the amount of energy given to the charge that … Continue reading Voltage and Current
Static Electricity: Uses and Dangers
It is important that you can describe and explain how static electricity is used, or avoided, in some real-life situations. A good way to recall example uses and dangers is to start from what they have in common; The uses all exploit electrostatic forces, which may either attract or repel objects.The dangers all involve sparks. … Continue reading Static Electricity: Uses and Dangers
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