Electricity (part 1)

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ELECTRICITY 1) ELECTRICITY AND MATTER. 1.1. Conductor and insulators 1.2. How to obtain electricity 1.3. The transport of electric energy 1.4. Effects of electric current 2)Electric quantities 2,1. Electric current 2.2. Voltage 2.3. Resistance. 3) Ohm's law 4)Electric circuits 4.1. Components of an electric circuit 4.2. Representation and symbols. 5)Types of circuits. 5.1. Series circuits 5.2. Parallel circuits 5.3. Series-parallel combination circuits

IES RĂ?O CABE Covadonga Yugueros Valbuena


1,Electricity and matter Matter is made of Atoms Charge

Protons

+

Neutrons

No Charge

Nucleus Atom

Electrons

Electric charge of an electron

Electron

Charge

-

Electric charge of a proton

Nucleus: â—? Protons â—? Neutrons


Electricity and matter II Usually matter is neutral because: because

Nº electrons = Nº protons neutral Nº electrons = Nº protons

Sometimes, it may happen that an electron migrates from one atom to another if given enough energy. Then we have n + 1 electro

-1e lectr on

Ion negative (Anion) Nº electrons 4 (-) Nº protons3 (+) +3 -4 = -1 Ion positive (Cation) Nº electrons 2(-) Nº Protons 3 (+) +3 -2 = +1


Electricy and matter III Positive Materials can have charge Negative

Charges with the same sign repel each other

Charges with the opposite sign attract

This causes static electricity, electricity that is the accumulation of charges on the surface of a material

Electric current is the flow of electrons. It is a continuous movement of electrons


1.1. Conductors and insulators Conductors a h nc i P

allow electric current to pass through them

Ă­ u aq

Insulators

don’t allow electric current to pass through them


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1.2. How to obtain electricity

In 1800 Alessandro Volta invented the electric battery when he proved that contact between different metals generated electric current

Tower of 60 discs of copper and zinc separated by wet fabrics in saltwater

In the S XIX Faraday discovered that moving a copper wire between magnets, appeared an electric current in the wire. 1st electric generator >> It produces electricity from the movement.

Zinc

Water + Saltwater

Copper

A N

S

Clic on the image


1.3. The transport of electric energy

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Electricity is generated at power stations: stations thermal, nuclear, hydroelectric, wind, etc. Most of the power stations use electric generators that use the motion of a turbine to transform it into electricity.

ge a m i e h t n o ck i l C

This electricity is transported through the grid to nearby population centers, where we obtain electricity by transformers.

la n e a h c Pin

en g i ma


1.4. Effects of electric current

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Electrical energy can be converted to other types of energy: light, heat, motion, sound, chemical and magnetic.

HEAT Calor

Electrons crash into the atoms of the material they are flowing. Part of the energy that they transport is transformed into heat when they crash. This is the Joule effect

The components used to produce heat

RESISTORS

Conductor wire rolled into a spiral


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LIGHT The temperature of an object increases with the electric current. When this increase is considerable, light begins to appear. At first it is red and then it becomes white at higher temperatures. This is incandescence

Some gases emit light when they carry an electric current Revestimiento de f贸sforo Vapor de mercurio Electrodos que emiten electrones

Incandescent and halogen bulbs Bombillas y hal贸genos Ampolla De vidrio

Gas inerte

Casco

Filamento

Contacto

Fluorescent tubes and low-energy bulbs Fluorescentes y bajo consumo


MOTION

Page 117 Movimiento

We can convert electricity to motion using a motor Motors are based on the electromagnetic effect of some materials

SOUND Sonido

We can produce sound effect through sirens, buzzers and bells We can transmit sound through microphone


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