Electricity and magnetism

1.Electricity• Everithingin nature is made of atoms, which contain particles called

protons and electrons. Protons have got a positive electric charge, and electrons have got a negative electric charge.

Neutral or charged?When there is an equal numberof protons than electrons in an objectis ellectricallyneutral.When there are more protons than electrons in an object it is positively charged.But if there are more electrons than protons, we say that the object is negativelycharged.Electrons can move from one object to another:Take a plastic ruler and a piece of woolen cloth.They are electrically neutral.Electrically charged objects will repel or attract each other, depending on their charges.

2. Electric currentElectric current is the movement of negatively charged electrons transformsthrough materials.Conductors are materials that conduct electric currents quite easily likecooper, aluminium, silber and other metals.Insulators are materials that don ´tIt can be generated in power plants and distributed to wherever we need it.1. A power plant generates electricity.2. A system of power lines distributes the energy as an electric current.3.We comsume the electrycity in our homes and industries.

Electric lamps transform electricity into light.Cookers transform into heat.Mixers and fans transform into movement.Radios transform into sound.

3.Electric circuitsElectric current is conducted along a pathand used to do work.

Conductor such as a metal wire conducts the electricity along the circuitPath.

A power source.

A switch is a device that closes and opens a circuit.

The resistor is a device that changes electricityInto another form of energy, such as light or heat.

4.MagnetismA magnet is an objectthat attrats iron and some other metals rocks arenatural magnets . We can also make artificial magnets.All magnets have got opposite ends, or poles.One end is the north magneticpole and the other ends is the south manetic pole.

If we put their opposite poles toghether, the magnets attract each other.

If we put their identical poles toghether, the magnets repel each other.

The earth´s magnetic fieldThe Earth is like an enormous magnet with two poles this creates amagnetic field around the planet.A compass is a device with a magnetic needle that always points to ourplanet´s magnetic north pole.This helps sailors and pilots to find their way to their destinations.

Electromagnets An electromagnet is a device that acts like a magnet when an electriccurrent passes through it.

An object made of iron, such as a nail.

A power source

A conductor , such as a metal wire

XD