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ORAL INTERVIEW (20p) 17 MAY (234) or 23 MAY (426) sign up in the list IN PAIRS 8-10 minutes You will be given a short text on ENERGY & THE ENVIRONMENT & you will have to: • Summarise the text • Answer some questions about the text ESSAYS ESSAY 1(Units 1- 4) MATERIALS DEADLINE: 12th APRIL ESSAY 2 (Units 5-10) ENERGY & THE ENVIRONMENT (150- 200 words) INCLUDE & UNDERLINE: • AT LEAST 15 GRAMMAR EXPRESSIONS from the list & • WORD FORMATION DEADLINE: 10th MAY PLEASE, follow the instructions personales.upv.es/ajaime You may deliver/collect your papers from my office door pocket SECTION II (Units 6-10) TOPIC: ENERGY & THE ENVIRONMENT • ORAL PRACTICE • and INTEGRATED GRAMMAR THROUGH TRANSLATION CONTENTS SECTION II • UNIT 6: ELECTRICITY (Rev connectors; Prepositions; PROCESSES: Purpose & Method) // U5- CAUSE/ALLOW • UNIT 7: POWER PLANTS(ACTIVE vs PASSIVE) • UNIT 8: ALTERNATIVE ENERGIES (Conditional cl. / OPINION) • UNIT 9: POLLUTION (DESCRIBING GRAPHS & DEGREE) • UNIT 10 WASTE DISPOSAL & RECYCLING (SEQUENCE) EXAM SECTION II = 35 points 26 MAY (30p)+ VIDEO test (5p) (pract sess 6) UNIT 6 ELECTRICITY Vocabulary • Electricity • Ways of generating electricity • Magnetism & Electromagnetism: Generators and transformers Grammar & Functions • • • • • Revision of connectors ORAL PRACTICE Prepositions PROCESSSES: purpose and method ALLOW/ CAUSE (U5 – p 60) LISTENING: electricity (p 67-68) • Electricity is a phenomenon of SOME CHARGED SUBATOMIC PARTICLES called electrons • WHEN THEY START MOVING FROM ATOM TO ATOM • An atom is the smallest particle OF WHICH ALL MATTER IS COMPOSED. • All atoms consist of a nucleus CONTAINING PROTONS AND NEUTRONS, • AROUND WHICH ELECTRONS ORBIT; • electrons orbiting farther from the nucleus ARE MORE EASILY DRAWN AWAY • therefore are more likely to move and CREATE AN ELECTRIC CURRENT • thus, AN ELECTRON IS NEGATIVELY CHARGED • whereas a proton is positively charged and NEUTRONS HAVE NO ELECTRICAL CHARGE • an atom is electrically neutral AS THERE ARE AS MANY PROTONS AS ELECTRONS IN ONE ATOM. • However atoms of different substances DIFFER FROM EACH OTHER DEPENDING ON THE NUMBER OF ELECTRONS AND PROTONS that they contain. • IN SPITE OF THE FACT THAT THE NUCLEUS IS THE SMALLEST PART OF AN ATOM, most of the atom’s weight is concentrated in its nucleus • An electron, ON THE OTHER HAND, weighs only about 1/1800 (one eighteen hundredth) OF THE WEIGHT OF A PROTON OR NEUTRON • Yet to produce the movement of electrons A DIFFERENCE IN POTENTIAL BETWEEN TWO POINTS must be created. • Electric sources SUCH AS BATTERIES, CELLS, GENERATORS, etc • change chemical, mechanical or other types of energy INTO ELECTRICAL ENERGY CONNECTORS (p 68) 1. Electrons are very light WHEREAS/WHILE protons and neutrons have most of the mass of the atom. 2. INSTEAD OF using the common metric units, the amstrong is preferred to measure atoms. 3. Electrons orbiting farther from the nucleus move to other atoms DUE TO THE FACT THAT/SINCE/AS they are more easily drawn away. 4. Unlike charges attract each other; THUS/THEREFORE/HENCE/AS A CONSEQUENCE, a positively charged atom will attract electrons from other atoms. 5. Electricity occurs DUE TO/ BECAUSE OF/OWING TO the movement of electrons. 6. DESPITE / IN SPITE OF the nucleus being the smallest part of an atom, it(the nucleus) contains most of its mass. 7. Electrons, protons and neutrons are called subatomic particles SINCE/DUE TO THE FACT THAT/AS they are smaller than an atom. 8. ALTHOUGH/ DESPITE THE FACT THAT the structure of atoms is similar for all elements, each element has a different number of electrons protons and neutrons. CONNECTORS (p 68) 9. UNLIKE/ AS OPPOSED TO/ CONTRARILY TO coal or solar energy, electricity is a secondary source of energy. 10. Research is underway to obtain superconducting properties at room temperature, WHICH is quite interesting for the field of telecommunications. 11. We can’t classify electricity AS a renewable or nonrenewable form of energy. 12. The failure has certainly appeared DUE TO/ OWING TO/BECAUSE OF impurities in the fuel. 13. With AC electricity, voltage can be readily changed, (THUS) making it more suitable for long-distance transmission than DC electricity 14. ALTHOUGH/ DESPITE THE FACT THAT gold is the best conductor, it is very expensive. THUS/ THEREFORE/HENCE/AS A CONSEQUENCE copper is used INSTEAD 15. An electron is two thousand times smaller in mass than a proton but its electrical charge is equal to THAT of a proton ELECTROMAGNETISM (p 68-69) 1. 2. 3. 4. PARAGRAPH 1 What is magnetism? Which material possesses magnetism? How can we magnetise magnetic materials? Which is an important characteristic of this property? ELECTROMAGNETISM (p 68-69) PARAGRAPH 2 5. What does dipolar mean? 6. What is the position of the poles in a magnet? 7. Explain the two effects of magnetism when we have two magnets 8. Why do they attract or repel? ELECTROMAGNETISM (p 68-69) PARAGRAPH 3 9. What is the magnetic field of a magnet? 10. What do the lines of force indicate? 11. Are the lines of force uniformly distributed? 12. What is the consequence of this distribution? 13. Which is the direction of the lines of force? 14. What is the consequence of it? ELECTROMAGNETISM (p 68-69) PARAGRAPH 4 15. What kind of relationship was discovered in the 19th century? 16. What did Oersted discover? 17. How did he discover this phenomenon? 18. What is a compass? 19. What did Oersted observe? 20.What was later discovered? 21. Mention examples of devices based on electromagnetism NOUNS (p 69) • • • • • • • • • • • • ADDition DIRECTion STRONG/strength DEVELOPment ABLE/ability ATTRACTion SCIENCE/scientist GENERATE/or-tion MAGNETism REPEL/repulsion DISCOVERy TRANSFORMer/ation ELECTROMAGNETS http://www.youtube.com/watch?v=EjfEiEwpuT8 • • • • • • • • • • • • 1-A piece of metal with two ends: North and South 2- A permanent magnet 3- Disadvantages 4- An electromagnet is the same as a permanent magnet 5- We get the N & S poles by passing a current around a wire wrapped around a coil (e.g. cardboard) 6- I get a North at one end and a South at the other as the current travels through it 7- I get no magnet 8- Because the electricity creates the magnetism 9 a)There is no metal in it (except the metal in the wire carrying the current) 9b)If I put in the center some iron it will make it much stronger(10-20 times stronger) 9c) A soft iron core (soft= easy to magnetize) =the coil will magnetize and demagnetize easily 10-I can switch it on and off = to pick up a piece of metal and then drop it PREPOSITIONS (p71-72) 1. A piece of iron becomes magnetized when it is brought NEAR a magnet 2. All substances that are attracted BY a magnet are capable OF becoming magnetized 3. The poles are located AT the ends of the bar magnet. 4. A Simple Generator consists OF a U-shaped magnet and a single loop of wire 5. Ordinary matter takes its form AS a result OF intermolecular forces BETWEEN individual molecules IN matter 6. The protons are basically trapped INSIDE the nucleus … Therefore, it is moving electrons that are primarily responsible FOR electricity. 7. Electromagnetism can be used to levitate a train ABOVE the track 8. WITHOUT electricity our lives would have come to a halt. PREPOSITIONS (p71-72) 9. The lines of force emanate FROM the north pole of a magnet, pass THROUGH surrounding space and enter the south pole. The lines of force then travel INSIDE the magnet from the south pole TO the north pole 10. Originally electricity and magnetism were thought of AS two separate forces. 11. An electri current flowing THROUGH a wire creates a circular magnetic field AROUND the wire, its direction depending ON that OF the current. 12. Some elecricity generation technologies result IN the creation of solid waste 13. A generator is a device that converts mechanical energy INTO electrical energy. The process is based ON the relationship BETWEEN magnetism and electricity 14. Whereas a synchronous motor's rotor turns AT the same rate AS the stator field, an induction motor's rotor rotates AT a slower speed than the stator field. PREPOSITIONS (p 72) Let´s have a look AT one of Faraday´s experiments, IN which he used a copper wheel and a horseshoe magnet. The wheel was located BETWEEN the poles OF the magnet. Electrical contacts were applied TO the wheel, both AT the centre and AT the edge of it. These parts were connected TO an ammeter BY means of wires IN order to detect the electrical current. Whenever the wheel rotated BETWEEN the ends of the magnet, an electrical current was shown ON / IN the ammeter´s display. When the wheel was made to turn IN the opposite direction, the needle OF the ammeter was deflected IN the opposite direction, too. Therefore, according TO this experiment, the direction of the current depended ON the turning of the wheel placed close TO a magnetic field. TRANSLATION (p73) • Some SCIENTISTS (WHO WERE) WORKING ON ELECTROMAGNETISM • discovered that the magnetic field of an electric current could BE STRENGTHENED BY SENDING A CURRENT THROUGH A COIL • A GREATER/HIGHER NUMBER OF TURNS IN THE COIL strengthens the magnetic field AS IT ALSO DOES a stronger electric current. • Placing the coil AROUND a piece of iron also increases the magnetism SINCE/AS THE IRON BECOMES MAGNETIZED • Not long after the DISCOVERY that A MAGNETIC FIELD COULD BE CREATED BY AN ELECTRIC CURRENT ), M. Faraday discovered that the reverse was also true. • When a closed loop of wire is moved through a magnetic field AN EMF (ELECTROMOTIVE FORCE) IS CREATED • THIS MAKES/CAUSES A CURRENT OF ELECTRONS Ø/TO FLOW THROUGH THE WIRE and is the basis for GENERATING electricity • To generate e.m.f. the wire must cut the LINES OF FORCE in the magnetic field. • Also THE FASTER THE WIRE IS MADE TO TURN, THE GREATER the production of e.m.f. TRANSLATION (p73) • Generators contain a stationary magnet, the stator, with a rotor placed BETWEEN ITS North & South poles • AS THE ROTOR TURNS the wires in it CUT THE LINES OF FORCE in the magnetic field of the stator. • With each half turn the flow of current is reversed producing alternating current (a.c.). The rotor IS DRIVEN BY A TURBINE, a machine with huge blades moved by water or steam produced BY BURNING COAL OR OIL • Transformers ARE ALSO BASED ON ELECTROMAGNETISM, • They consist OF two COILS of wire WOUND around pieces of iron. • Current is supplied to a transformer through the primary coil and taken from the secondary. When an ALTERNATING CURRENT FLOWS THROUGH THE PRIMARY the constant reversal of electron flow produces a changing magnetic field that creates a current in the secondary coil. • When the primary coil has MORE TURNS THAN THE SECONDARY voltage is decreased; • when the secondary coil has more turns than the primary, the secondary voltage INCREASES/GOES UP/RISES. PROCESSES (p75) • The result (PURPOSE) (What for?) • The way of carrying out the process (METHOD) (How?) • COMMON VERBS used in processes (U5 p 57) • • • • C RESULTS IN C BRINGS ABOUT C GIVES RISE TO C LEADS TO E dar como resultado E provocar, E implicar, suponer E lleva/conduce a • C MAKES X / BECOMES + ADJ resulta/ lo hace … ADJ • C CAUSES/ALLOWS E hace que (+Vb) PURPOSE (WHAT FOR?) (p75) • TO (NOT TO) • SO AS TO (SO AS NOT TO) + INFINITIVE • IN ORDER TO (IN ORDER NOT TO) para+inf FOR + NOUN = For more information, call…. This place is for exhibitions • FOR THE PURPOSE OF • WITH THE AIM OF • WITH THE OBJECTIVE OF + GERUND • SO THAT + SENTENCE (S+Vb) para que (In order) to generate electricity, we use different energy sources Turn the lights off so as not to waste electricity The new system raises the turbine’s condenser temperature so that all the condensation energy can be used for district heating METHOD (HOW?) (p 75) • BY • • • • • + VB -ING gerundio BY por, por medio de, mediante,… BY MEANS OF THROUGH + NOUN WITH WITH THE HELP/ASSISTANCE OF Electricity is generated from water by using dams and by capturing the potential energy of water Generators produce electricity by means of a principle discovered in the early 1830's Energy savings through improved mechanical systems INSTRUCTIONS (p 76) A F4: We start by winding the armature, the part of the motor that moves. To make the armature nice and round, we wind it on a cylindrical coil form, such as a small battery. Don't try to be neat, a little randomness will help the bundle keep its shape better. B F5: Now carefully pull the coil off of the form by holding the wire so that it doesn't spring out of shape. To make the coil hold its shape permanently, wrap each free end of the wire around the coil a couple of times, making sure that the new binding turns are exactly opposite each other, so as to allow the coil to turn easily on the axis formed by the two free ends of wire, like a wheel. C F2: Hold the coil at the edge of a table in order to keep it straight (not flat on the table), with one of the free wire ends lying flat on the table. With a sharp knife, remove the top half of the insulation from the free wire end. Be careful to leave the bottom half of the wire with the insulation intact. The top half of the wire will be shiny bare copper, and the bottom half will be the color of the insulation. Do the same thing to the other free wire end, making sure that the shiny bare copper side is facing up on both wire ends INSTRUCTIONS (p 76) D F·3: The next step is to make the axle supports. In order to make the supports, take a stiff piece of bare wire (copper or brass will work, as will a straightened paper clip) and bend it around a small nail to make a loop in the middle. Do the same to another wire, so you have two supports. E F1: Attach the support wires securely to the battery holder by winding the free ends several times through the small holes in the plastic at each end. Bend the support wires so the rings are just far enough apart for the armature to spin freely. Bend them apart a little and insert the armature into both rings, then bend them back so that they are close to the coil, but not touching it. Insert the battery into the holder. Place the magnet on top of the battery holder just underneath the coil. • Note that there is a strip of paper stuck in between the battery and the electrical contact in the holder. This is the on/off switch. Remove the paper to allow electricity to flow into the motor, and replace the paper in order to stop the motor. CAUSE/PERMIT/PREVENT (U5 p60) CAUSE: TO CAUSE + OBJ + TO INFINITIVE TO MAKE + OBJ + BASE FORM OF THE VERB hacer que + frase PERMIT: TO ALLOW + OBJECT + TO INFINITIVE TO PERMIT + OBJECT + TO INFINITIVE TO ENABLE + OBJECT + TO INFINITIVE TO LET + OBJECT + BASE FORM OF THE VERB permitir que + frase PREVENT: TO PREVENT + OBJECT + FROM + -ING TO AVOID + OBJECT + FROM + -ING TO STOP + OBJECT + FROM + -ING TO KEEP + OBJECT + FROM + -ING impedir que + frase EXERCISE CAUSE/ALLOW/PREVENT (p60) 1. The recommendation of various alternatives can permit the company to determine which one is best for the particular situation. 2. Chemical degradation is a process in which additives cause plastics to crumble away. 3. The composite fibers prevent some kinds of brittle materials from cracking. 4. Known as rapid solidification, the process causes the atoms to freeze in place before they can align in a crystalline lattice. 5. Lighter and more heat tolerant than metals, ceramics permit the engine to run hotter, and therefore more efficiently. 6. When ceramic is unable to bend, a strong impact will cause it to crack. 7. Stress ceramics prevent the crystalline planes from deforming. 8. Superconductors permit electrons to flow indefinitely. 9. Carbon dioxide permits the infrared rays to pass through the atmosphere but prevents them from leaving again. 10. Insulators prevent electrons from flowing through them. ORAL PRACTICE: DRY CELL EXPLAIN: • • • • Purpose of a dry cell Describe main components (shape, materials, …) Function of each component How a dry cell works UNDERLINE: • Key words • Key verbs ORAL PRACTICE: DRY CELL ORAL PRACTICE: DRY CELL This dry cell is the most common type of cell. It consists of the positive pole, which is a carbon rod surrounded by a mixture of carbon powder and manganese dioxide. This mixture is the depolarizer, which prevents hydrogen bubbles from forming on the anode, avoiding the reduction of the activity. At the top of the carbon rod is a brass cap, which acts as the positive terminal, allowing electrons to flow. The carbon rod and the depolarizer are placed inside a porous bag, and between the bag and the container we find the electrolyte, i.e., the chemical substance which allows the chemical reaction to take place. This electrolyte is a paste and not a liquid and fills the container. The zinc container also acts as the negative pole, to complete the circuit. The other only element left is the sealing compound at the top of the container to avoid all the other components of the cell from going out VIDEO1: MAGNETIC CIRCUITS (p77) • This is the well known display of THE MAGNETIC FIELD of a permanent magnet displayed BY the DISTRIBUTION of iron filings. • The whole of this programme is ABOUT displaying MAGNETIC FIELDS in one way or another. • Of course the trouble with magnetic fields is that you cannot actually see them. So, what I'll try to do in this programme is to DEMONSTRATE them to you and to show THAT THEY CAN BE SHAPED AND CONTROLLED BY showing their effects RATHER THAN the fields themselves. VIDEO2 : MAGNETIC CIRCUITS (p77) • This particular display of THE MAGNETIC FIELD OF A PERMANENT MAGNET shows the field very clearly … • …because the iron filings distribute themselves ALONG THE DIRECTIONS OF THE LINES OF FORCE, • …if that's the NORTH POLE and that's the South pole, the LINES OF FORCE RUN FROM THE N POLE TO THE S POLE • … and the iron filings distribute themselves ALONG these lines pointing TOWARDS the pole pieces of the magnet. So in that particular instance the field is very clearly demonstrated. VIDEO3 : MAGNETIC CIRCUITS (p77) • I can represent this with a diagram. HERE THERE IS A DIAGRAM OF A PERMANENT MAGNET, N AT one end and S. AT the other, • …and the lines of force are running FROM THE N POLE TO THE S POLE, roughly along the same pattern as you saw in the iron filings demonstration. • So, this is A SIMPLE GRAPHICAL REPRESENTATION of the kind of thing that happens with a permanent magnet. VIDEO 4: MAGNETIC CIRCUITS (p77-78) • Now, let's put two permanent magnets side BY side. THIS IS THE DISTRIBUTION OF LINES OF FORCE THAT you get. They're squeezed together BETWEEN these two magnets, when the N is NEXT TO N, and S. is NEXT TO S. What does this actually mean IN PRACTICE? VIDEO 5: MAGNETIC CIRCUITS (p77-78) • I can show this with some actual permanent magnets that I have here, THEY ARE PERMANENT MAGNETS MADE OF STEEL with N pole marked at each end so that this resembles the diagram you just looked at. So if I push the two together quite clearly ONE IS REPELLING THE OTHER; if I press the two together side by side, it is firmly pushed away. So, THERE IS A FORCE OF REPULSION HERE. Let's go back to the diagram to see how we might explain it. • You see here the lines are apparently compressed and they actually behave very much as though they are ELASTIC AND COMPRESSIBLE so when lines of force get compressed like that they do represent A FORCE OF REPULSION shown here by these white arrows. VIDEO 6 : MAGNETIC CIRCUITS (p78) • If I TURN THE MAGNETS ROUND so that N is now FACING S I'm sure you are very familiar with the fact they attract ONE ANOTHER like this. This again can be shown ON the diagram. Here the LINES OF FORCE now running FROM N TO S are pulling the magnets together, there's A FORCE OF ATTRACTION AS again shown by the arrows. • The first main point I want to get over is that actually THESE FIELDS CAN BE QUITE EASILY SHAPED BY USING PIECES OF IRON to do this. VIDEO 7 : MAGNETIC CIRCUITS (p78) • Here I've got some pieces of iron. They ARE NOT MAGNETIC at all, they DON'T ATTRACT EACH OTHER, but if I put them along side these magnets like this, ALONG one side so the two magnets face again, the two N poles REPELLING, the two N poles OPPOSITE each other, so they should repel EACH OTHER, what do you think will happen? • Let's see. NOTHING AT ALL. The FORCE OF REPULSION has been almost completely removed. So, what happened is that the MAGNETIC FIELD that was filling the gap BETWEEN the magnets has been shunted away down the iron; IRON IS A VERY MUCH MORE ATTRACTIVE route for magnetic fields than does air; so it's been shunted away and THE FORCE OF REPULSION IS REMOVED. VIDEO 8 : MAGNETIC CIRCUITS (p78) • • • Here you see the magnetic lines which were in the gap BETWEEN them as they are still OUTSIDE the gap but now the lines have been shunted THROUGH the iron represented BY this light grey area, shunted through there, LINES AGAIN RUNNING FROM N TO S, in both magnets and the gap between them, you see, has no lines of force left, SO THERE IS NO FORCE OF REPULSION LEFT either. Now I can demonstrate this effect rather more dramatically with a different pair of magnets. Here I have a ferrite magnet. IT IS A MEGNETIC MATERIAL, ceramic in nature and CAN BE MAGNETIZED quite strongly. Here you see there are two rings, one ABOVE the other, the upper one is being supported BY THE MAGNETIC FORCE exerted BY the lower one. All the magnetic forces interreact to be more exact. This kind of levitation of a body DUE TO magnetic field will be demonstrated in the next TV programme where the method is used to levitate a train ABOVE the track. But I can show you how the field can be shunted away FROM these two by taking these pieces of iron again and slipping them between the magnets. As I put them in, THE MAGNETIC FIELD IS GRADUALLY REMOVED until there isn't any left and the upper magnet sinks DOWN onto the lower one, and THERE IS NO FORCE OF REPULSION left; removing these pieces of iron restores the levitation of the ring magnet. PARA PARA + NOUN For somebody=> for a present for you For some purpose => for the food is for the party what for? indicating comparison => for it's good for what it costs Time => for, by, around an appointment for Monday it’ll be ready by April Direction => to, towards they're heading towards the river to the right/left PARA + INFINITIVO (Purpose) To, In order to, so as to + INFINITIVE he does it to annoy you ; in order not to be seen too young to understand PARA QUE+ SENTENCE so that Place the test tube so that it is below the water FOR FOR = PREPOSITION (+ NOUN) • indicating a goal: para, de, por food for the party, cure for cancer to study for a test for more information, call… time for dinner , to travel for pleasure, • indicating a recipient : para a gift for you • indicating duration : por, durante he's going for two years • indicating a particular time : para, por the wedding is planned for April enough for now • indicating amount or value : por, de a check for $100 FOR IS NOT USED TO INTRODUCE THE AGENT OF THE PASSIVE POR • Por causa de, debido a => because of, due to, owing to I arrived late because of the traffic • Por un lugar = by, along I stopped by your house; along the coast • durante ( tiempo) => for, during they stayed there for a week • por medio de => by means of , with (tool) Voltage is changed by means of/with transformers • a través de => through Water flows through the pipes • AGENT OF THE PASSIVE=> BY The pyramids were built by the Egipcians • LISTENING (p 74) 1. THERMAL, LUMINOUS, CHEMICAL, MAGNETIC 2. IT MAY HEAT THE CONDUCTOR 3. ELECTRIC MOTORS AND GENERATORS 4. NO. EG. DOMESTIC APPLIANCES (ELECTRIC COOKERS) AND MANY INDUSTRIAL PROCESSES 5. LIGHT 6. THE CONDUCTOR BECOMES INCANDESCENT 7. THE FILAMENT OF A LIGHT BULB 8. WHEN A CURRENT IONIZES A GAS 9. GREENISH-BLUE LIGHT LISTENING (p 74) 10. AN ELECTRIC CURRENT CAN SEPARATE A CHEMICAL COMPOUND INTO ITS COMPONENTS 11. BY ELECTROLYSIS OF SALT WATER 12. TO BREAK DOWN WATER INTO HYDROGEN AND OXYGEN 13. SULPHURIC ACID BECAUSE PURE WATER DOES NOT CONDUCT WELL 14. A MAGNETIC FIELD AROUND IT 15. 1-MAGNETIZE MAGNETIC MATERIALS AND ATTRACT THEM TO THE CONDUCTOR (e.g. = RELAYS) 16. 2- IF THE MAGNETIC FIELD IS CUT BY ANOTHER CONDUCTOR, AN ElectroMotiveForce WILL BE INDUCED IN THAT CONDUCTOR (e.g.= TRANSFORMERS AND GENERATORS) 17. 3-IF A CURRENT-CARRYING CONDUCTOR IS PLACED IN THE MAGNETIC FIELD, A FORCE WILL BE EXERTED ON IT (e.g.= MOTORS) GUIDED WRITING (p77) 1- Materials can be divided into conductors and insulators depending on whether they permit electrons to flow easily/ how easily they permit electrons to flow GUIDED WRITING (p77) 2- Most metals are good conductors because they have (a) low resistance (to electricity) 3-However, copper is the most commonly used metal in wires due to its low resistance. In addition, its malleability and ductility enable us to make coils GUIDED WRITING (p77) 4- The cross section of a wire is also important. Thus, a thick wire offers a low resistance to the flow of electricity, whereas a thin wire increases resistance. Thick wires are therefore used for distributing / to distribute electricity from power plants to our houses. GUIDED WRITING (p77) 5- On the other hand, thin wires are used in lamps because their high resistance is what is used for making / to make lamps shine