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
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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
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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
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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