Warning! High Levels Of Electricity

Electricity is everywhere. But what is it? Let’s find out.

Electricity is the flow of tiny particles called electrons. They are one of the particles that make up an atom (see last week’s issue). The other two, protons and neutrons, are stuck in the centre and usually don’t move. But electrons are free to move from atom to atom, causing an electrical current. If an atom has fewer electrons than it wants, it is called positively charged. It tries to pull electrons from neighbouring atoms that have more electrons than they want and are called negatively charged.

If you get the electrons to flow through an electrical component, some of the energy can be converted to another form of energy like  light, heat, sound or movement.

So how do we get this electricity to flow? Well, we have to make a circuit. In it there is an energy source liken a battery. Electrons get pushed out one end of the batteryand flow from atom to atom until they reach the other end. The wire is made of the most conductive material so that the electrons flow better. The most conductive element is silver, but because this is expensive, copper is used instead.

What are you going to have for lunch today? Maybe something microwaveable. But how does a microwave cook food? It’s all down to that ‘tricity again...

1. Inside the strong metal box, there is a microwave generator called a magnetron. When you start cooking, the magnetron takes electricity from the power outlet and converts it into high-powered radio waves.The magnetron blasts these waves into the food compartment through a channel called a wave guide.
2. The food sits on a turntable, spinning slowly round so the microwaves cook it evenly.
3. The microwaves bounce back and forth off the reflective metal walls of the food compartment, just like light bounces off a mirror. When the microwaves reach the food itself, they don’t simply bounce off. Just as radio waves can pass straight through the walls of your house, so microwaves penetrate inside the food. As they travel through it, they make the molecules inside it vibrate more quickly.
4. Vibrating molecules have heat, so the faster the molecules vibrate, the hotter the food becomes. Thus the microwaves pass their energy onto the molecules in the food, rapidly heating it up.

There were lots of great electrical inventions, but who invented them? That’s all down to Michael Faraday...

Michael Faraday (1791-1897) was a Victorian chemist and physicist who was the son of a poor blacksmith. Although he had very little (and bad) schooling, he taught himself by reading the books he binded as a bookbinder, and did his own experiments after work.

Michael became an assistant to the chemist Humphry Davy in 1813, and took him around Europe where he met some of the greatest scientists of all time.

Mike’s most important work was the invention of the electric motor in 1821. He also worked on magnetism, and also discovered how to make electromagnets, which are used in electric generators.

Apart from his work in physics, Faraday also made discoveries in chemistry, like how to make stronger steel.

A generator is the opposite of a motor. A motor turns electricity into movement, but a generator turns movement into electricity. For example, in a wind turbine, thse wind blows the blades around and this is turned  into electricity. This happens by a rotor moving through a magnetic field, which creates electrical current.