• Author / Uploaded
• José María Nogueras Valdivieso

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NATURAL SCIENCE 5th LEVEL UNIT 7: ELECTRICITY AND INVENTIONS 1. What’s electricity? Electricity is formed when a part of each atom, called an electron, moves from one atom to another. -

What’s an atom made up of? The nucleus is made up of protons and neutrons. The protons have a positive electric charge. The electrons revolve around the nucleus, so they are constantly moving. They have a negative electric charge.

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What’s static electricity? Static electricity is the movement of electrons between two materials. Electrons can move easily between materials when we rub them together. This creates static electricity. Opposite charges attract each other. Objects with the same electric charge are repelled

2. What’s electric current? Electric current is the movement, or flow, of electrons between atoms. Some types of matter have electrons that move easily from one atom to another. We call these electrical conductor because electricity can flow easily through them. Metals are an example of electrical conductors.

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Electricity and magnetism. When electric current flows through wires, a magnetic field is produced. This happens because negatively charged electrons are moving through the wire. We can make the magnetic field stronger by winding the wire into a coil around an object made of iron. This forms an electromagnet.

3. Why do we need electric circuits? An electric circuit is a close loop or circle. Electricity will only flow if the circuit is close. If the circuit is broken or the switch is off, the current stops flowing. -

Types of circuits

SIMPLE CIRCUIT The battery is connected to the light bulb, the light bulb to the switch and the switch to the battery.

SERIES CIRCUIT Two or more light bulbs are connected to one batttery, but all are connected within the same circuit.

PARALLEL CIRCUIT

A parallel circuit forms two or more cicles, one bigger tan the other. Each circuit has a light bulb. All the circuits are connected to the same battery.

4. How do we use electricity? Electricity is used in many ways in our homes, schools and workplaces. -

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How does electricity get to our homes? Electricity is generated in power stations. From the power station, the electricity travels along big cables to our homes. At the place where electricity enters our house, there is a fuse box. How do we use electricity in our homes? From the fuse box, the electricity travels through wire to all the light switches and sockets in our home.

5. Who was Thomas Edison? Thomas Edison was an American inventor. His most important inventions were the electric light bulb, motion pictures and recorded music.