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Electricity No Messing Resources c Menu • Household Plugs & Fuses • Power & Fuses • Static Electricity • Charge • Dangers of Static • The Cost of Electricity • Uses of Static • Magnetism • Circuit Symbols • Electromagnets & Devices • Current • Generating electricity • Voltage • Electric Motors • Resistance • Transformers • Summary Table • Power Stations • Electrolysis • National Grid • AC & DC • Related Websites No Messing Resources c Static Electricity No Messing Resources c Static Electricity Static electricity is about charges that are NOT free to move. This causes them to build up in one place and it often results in a spark or shock when they finally move No Messing Resources c How Can Materials Become Charged? When two insulating materials are rubbed together, electrons can be ‘scraped off’ from one material to another. This results in a positive static charge on one and an equal but opposite negative static charge on the other No Messing Resources c Which Way Are the Electrons Transferred? This depends on the materials involved Negatively charged rod Positively charged cloth +++++ +++++ +++++ The electrons have moved from the cloth to the rod No Messing Resources c Only Electrons Move A positive static charge is always caused by electrons moving elsewhere Just think about it…the electrons are on the outside of the atom…. the protons are held in the centre Protons No Messing Resources c Electrons Like Charges Repel and Opposite Charges Attract. - ---- ------ The balloons both have the same static charge and will repel each other No Messing Resources c The Van de Graaff Generator can make your hair stand on end! - - - - - - - - - - - - - - - - - - - Each hair has the SAME charge and therefore repels the others No Messing Resources c Attraction The comb has been charged by friction and has gained electrons (it has a negative charge) It induces a separation of charges on the paper and attracts the pieces No Messing Resources c Explain what is happening here…. - -- --- - - -- - -- -- Has the balloon ‘gained’ or ‘lost’ electrons? No Messing Resources c Explain What You Think Is Happening No Messing Resources c Why is the water ‘bending’? Charged comb No Messing Resources c The Van de Graaff Generator As electrons are rubbed off the belt they collect on the domes. If a big enough charge is built up then the voltage becomes high enough to ionise the air molecules and the electrons ‘jump’ to Earth as a spark No Messing Resources c Can you see the mad scientist? Return to menu Dangers of Static Electricity No Messing Resources c Dangers of Static As the fuel moves through the pipe it gains electrons from the pipe, making the fuel negative and the pipe positive. This can result in a spark and ultimately an explosion No Messing Resources c The helicopter can become charged by the friction of the rotor blades against the air For safety reasons, the rescuer has a conductor attached below him to discharge the current safely No Messing Resources c How Can We Refuel Safely? Refuelling can be carried out safely if either the fuel tank is earthed with a copper rod or the tanker is connected to the plane by a copper conductor No Messing Resources c How Do We Get Thunder & Lightning? Particles inside a thunder cloud move around and get charged by friction. The heavier particles accumulate at the bottom of the cloud gaining a negative charge. These are attracted to the earth and we get a BIG SPARK! No Messing Resources c Lightning – Did you Know? A bolt of lightning travels at 120 kilometres per second. One bolt has enough energy to run the whole of the UK for a week It can heat the air around it to 28,000 0C (Several times hotter than the surface of the sun) About a hundred lightning bolts hit the Earth every second No Messing Resources c Return to menu Uses of Static Electricity No Messing Resources c Can We ‘Use’ Static Electricity? We use static electricity in dusters and floor wipes to attract the dust No Messing Resources c Electrostatic Paint Spraying The paint is given a positive charge making each drop repel as they are ‘like’ charges. The car being sprayed is given a negative charge (or connected to earth), so the droplets are attracted to it No Messing Resources c + + + + + + - -- -- - -- The Advantages of Electrostatic Paint Spraying Are: • Less paint is wasted • A more even coat of paint is achieved No Messing Resources c How does a Photocopier use Static Electricity to print documents? No Messing Resources c 1) Inside the photocopier A light sensitive drum is given a negative charge No Messing Resources c 2) An image of the document is projected onto the plate The bright areas lose their charge but the dark areas keep it No Messing Resources c 3. Powdered ink (called toner) is attracted to the charged areas No Messing Resources c 4) A blank sheet of paper is pressed against the paper and picks up the ink No Messing Resources c 5) The paper is heated so that the powdered ink melts and sticks to the paper No Messing Resources c Return to menu Circuit Symbols No Messing Resources c Identify the Circuit Symbols A Filament lamp/ Bulb A Cell A Battery of 2 Cells A Switch A Battery of a number of cells A fixed Resistor No Messing Resources c Identify the Symbols Variable Resistor L.D.R Thermistor Fuse Heater Loudspeaker No Messing Resources c Identify the Circuit Symbols A V M Ammeter L.E.D Voltmeter Motor No Messing Resources c Draw the Circuit Symbols Component Circuit Symbol Thermistor L.D.R Fuse L.E.D No Messing Resources c Return to menu Current No Messing Resources c Electrons Flow in the Opposite way to the Conventional Current -+ Electrons are negatively charged and therefore flow from negative to positive e- No Messing Resources c We normally say that the current flows from positive to negative Current Current is the FLOW OF ELECTRONS AROUND A CIRCUIT In metals, current is carried by electrons The unit of current is the ampere (A) We use an ammeter to measure current No Messing Resources c Ampere This is the scientist AMPERE. He studied current in circuits and gave his name to the unit of current No Messing Resources c Current in a Series Circuit 2A 2A 2A The Current in a Series Circuit is the Same at Every Point No Messing Resources c In a series circuit the bulbs are all the same brightness If the bulbs are of the same rating! No Messing Resources c Current Questions A B C 1) The current reading for bulb B is 2A. What are the readings for bulbs A and C? 2) Bulb suddenly fails. What happens to bulbs A and C? No Messing Resources c What Is the Current at This Point? 6A No Messing Resources c Brightness of Bulbs in a Series Circuit If a cell is added the current will increase and the bulb gets brighter No Messing Resources c Brightness of Bulbs in a Series Circuit If a bulb is added the current will decrease as there is greater resistance in the circuit and the bulbs get dimmer No Messing Resources c Current in a Parallel Circuit A PARALLEL circuit has more than one path for the current to flow through Bulb A Bulb B Assuming both bulbs are the Same…they will be the same brightness No Messing Resources c Current in a Parallel Circuit The Advantages of a parallel circuit are: Bulb A Bulb B • If one bulb fails ….the other will remain on • Both bulbs can be switched on separately No Messing Resources c Current in a Parallel Circuit 6A 6A 2A 2A 2A No Messing Resources c The total flow of current is equal to the total current from all of the branches What is the ammeter reading? 9A 3A 3A 3A No Messing Resources c Return to menu Voltage (Potential Difference) No Messing Resources c Voltage Is the Driving Force That Pushes the Current Around the Circuit We need Energy to push the electrons around the circuit. In this case the energy comes from the lemon (in the form of chemical energy) No Messing Resources c Potential Difference/ Voltage This is VOLTA. He studied the driving force that pushes current around a circuit. He gave his name to the unit of Potential Difference The unit of Potential Difference is the VOLT (V) No Messing Resources c Voltage in a Series Circuit 12V 4V 4V 4V 12V No Messing Resources c The voltage in a series circuit is shared across each component. The sum of the voltages across each component equals the source voltage What Is the Voltage? ?V 8V 8V 8V ?V No Messing Resources c 6V 6V 6V Voltage in a Parallel Circuit The voltage is the same across all components in parallel No Messing Resources c 9V What Is the Voltage? ?V ?V No Messing Resources c Return to menu Resistance No Messing Resources c Resistance Resistance is anything in a circuit that restricts the flow of current It can be calculated using Ohm’s Law: Resistance = (Ohms) The unit of Resistance is the Ohm Voltage (V) V Current (A) I No Messing Resources c x R Complete the meter readings 6A 12V A2 A3 V1 A1 V2 No Messing Resources c V3 Calculate the resistance ? 3A 12V No Messing Resources c Current-Voltage Graphs Show Resistance A Resistor at constant temperature I V Different wires have different resistances The current through a resistor at constant temperature is proportional to the voltage No Messing Resources c Current-Voltage Graphs Show Resistance I V A Filament Bulb As the temperature of the filament increases, the resistance increases – hence the curve No Messing Resources c Current-Voltage Graphs Show Resistance Current will only flow through in ONE DIRECTION I V A Diode (It has very high resistance in the reverse direction) No Messing Resources c Resistance in Wires – Cross Sectional Area Thin wires have more resistance than thick wires Halving the cross sectional area of a wire doubles its resistance because there is half as much space for the electrons to move No Messing Resources c Resistance - Length of Wire Doubling the Length of a wire Doubles its resistance because the electrons have twice as far to move No Messing Resources c Resistance - Material Different materials have different resistances. For Example: A nichrome wire has more resistance than a copper wire of the same size (the atoms in nichrome hold the electrons more tightly than copper atoms) No Messing Resources c Dark 1A The Light Dependent Resistor Light 5A The resistance of the LDR depends on the amount of light falling on it. Its resistance decreases as the amount of light falling on it increases No Messing Resources c The Thermistor 1A COLD 5A WARM The resistance of a thermistor depends on its temperature. Its resistance decreases as the temperature of the thermistor increases No Messing Resources c Explain Fully How the Following Work 1) A Diode 2) A Thermistor 3) A Light Dependent Resistor No Messing Resources c Return to Menu Summary: Current, Voltage, Resistance, Series & Parallel No Messing Resources c How are voltmeters & Ammeter connected in a circuit? A Ammeters are always connected in SERIES Voltmeters are always connected in Parallel V No Messing Resources c Summary Table Current Is the flow of electrons around a circuit Voltage Is the driving force that pushes the current around. Is anything in a circuit which slows the flow down Resistance No Messing Resources c There is a Balance…. If you increase the Voltage – then more current will flow If you increases the Resistance – then less current will flow No Messing Resources c Which Is the Series and Parallel Circuit A * Current is THE SAME at any point * Voltage SPLITS UP over each component B * Current SPLITS UP down each branch * Voltage is THE SAME across each branch No Messing Resources c Return to Menu Electrolysis No Messing Resources c In Electrolytes the Current Is Carried by Both Positive & Negative Charges +The negative ions move towards the positive electrode - - - + + - + + + + No Messing Resources c The Positive ions move towards the negative electrode The Process Where Current Is Carried by Both Positive & Negative Charges Is Called ELECTROLYSIS +The positive electrode is called the ANODE - - - + + - + + + + No Messing Resources c The negative electrode is called the CATHODE Which way would copper ions move? Electrolysis in More Detail Each ion carries the same charge, So: The Mass Deposited is Proportional to the Total Charge Transferred Charge = Current x Time Longer time, a greater mass is deposited So, if a Higher Current flows for a No Messing Resources c Uses of Electrolysis Depositing a metal by electrolysis as shown in the picture is called ELECTROPLATING No Messing Resources c Lots of gold & silver ornaments are electroplated because less ‘precious’ metal is used Submarines and Space Vehicles use Electrolysis…. …..To split water into Hydrogen & Oxygen • The Hydrogen is used as a fuel • The Oxygen for breathing No Messing Resources c Electrolysis Questions 1) A current of 3A flows through some copper chloride for 1 minute and 0.01g of copper is deposited at the negative electrode. a) How much would be deposited if the current was increased to 6A? b) How much would be deposited if the current was kept at 6A and the experiment was left for another minute? c) How much charge flowed in question (b) above? No Messing Resources c Return to menu AC & DC No Messing Resources c Alternating Current (AC) Voltage The current changes direction 50 times every second (frequency = 50Hz) AC is easier to generate than DC No Messing Resources c Time Direct Current (DC) The current only flows in one direction Voltage Time If the cell is reversed the current flows in the opposite direction No Messing Resources c Return to menu Household Plugs & Fuses No Messing Resources c Wiring a plug Earth Wire 3 4 Fuse Neutral Wire 2 5 Live wire Cable grip 1 6 Cable No Messing Resources c Errors in Wiring Plugs 1. Bare wires showing 2. Proper fuse not installed 3. Earth Wire not connected 4. Live & Neutral wrong way round 5. Cable Grip loose No Messing Resources c Dangerous Practices With Mains Electricity 1. Broken Plugs & Frayed Cables 2. Plugs & Cables near water 3. Overloaded sockets 4. Wet hands whilst using electricity No Messing Resources c The Earth Wire Earth wires are always used in appliances with a metal case. If a fault develops in the appliance causing the live wire to touch the case, there is a surge in the current down the earth wire. This causes the fuse to blow. No Messing Resources c Live & Neutral The Live wire alternates between high positive and high negative voltage with an average of about 230V The neutral wire is always at 0V. Electricity normally flows in and out of the live and neutral wires only No Messing Resources c Fuses Symbol Car fuses A Fuse is a deliberate weak spot in a circuit No Messing Resources c How Does a Fuse Work? Fuses are designed for safety. If a fault develops causing the live and neutral (or earth) wire to cross, a large current flows through the fuse and causes it to melt. This breaks the circuit and protects the appliance and user. No Messing Resources c Complete the descriptions….. Fuse A deliberate weak spot. Melts and breaks the circuit with too much current Earth Wire Neutral Wire Live Wire Cable Grip Casing Brass Pins No Messing Resources c Return to Menu Power & Fuses No Messing Resources c Power, Current & Voltage Power is “the rate of doing work”. The amount of power being used in an electrical circuit is given by: Power = voltage x current (W) (V) P (A) The unit of power is the watt (W) No Messing Resources c V X I Power and Fuses Complete the following table: Appliance Power Rating Voltage (V) (W) Toaster 950 230 Electric Fan Heater 2200 230 Hairdryer 330 230 Floor Cleaner 1050 230 Computer 200 230 HiFi 80 230 No Messing Resources c Current (A) Fuse Required (3, 5 or 13A) Return to Menu Charge No Messing Resources c How Do We Calculate ‘Charge’? The unit of ‘Charge’ is the Coulomb (C) We can work out how much charge flows in a circuit using the equation: Charge = current x time (C) (A) The symbol for charge is Q No Messing Resources c (s) Q I X T Questions 1) A circuit is switched on for 30s with a current of 6A. How much charge flowed? 2) During electrolysis 3A was passed through some copper chloride and a charge of 600 Coulombs flowed. How much time was the experiment on for? 3) A light is switched on for 30 minutes. It works on a current of 0.5A. How much charge flowed? No Messing Resources c Are Energy & Charge Linked? The energy that flows in a circuit depends on the amount of charge carried by the electrons and the voltage pushing the charge around Energy Transferred = Charge x Voltage (J) (C) E V X Q No Messing Resources c (V) Questions 1) A portable cd player has a voltage of 5V and a charge of 100C flowing through it. How much energy has been transferred? 2) A table light is attached to a 12V circuit. It has a charge of 1200C flowing through it. If the lamp is on for 15 minutes calculate a) the current b) the resistance c) the energy supplied to the bulb. No Messing Resources c Return to menu The Cost of Electricity No Messing Resources c The kiloWatt hour (kWh) is a unit of Electrical energy. In this case the meters are showing how much electrical energy has been used in a home No Messing Resources c How do we calculate the cost of electricity? This depends on: • The POWER RATING of the appliance and • HOW LONG you leave it on for. Electricity is measured in “units”, also called “kilowatt hours” (kWh). No Messing Resources c For electrical devices we can use the equation: POWER = (W) Energy transformed (J) time taken (s) Appliances such as toasters, irons & TVs have a power rating marked on them either in watts or kilowatts. 1 kiloWatt (kW) = 1000 watts 1 Watt = 1 Joule per second No Messing Resources c Consider this kettle. In 5 seconds, the kettle takes 10,000 Joules of energy from the mains supply. What is its power? Power = Energy Transformed Time taken = 10,000 / 5 = 2000W (or 2kW) No Messing Resources c Calculate the cost of leaving a 600W computer on for 120 minutes. (The cost of each unit of electricity is 8 pence) Number of UNITS used = Power (in kW) x Time (in hours) = 0.6 kW x 2 hours = 1.2 units COST of Electricity = Number of Units used x price per unit = 1.2 units x 8 pence = 9.6 pence No Messing Resources c Return to menu Magnets No Messing Resources c What Is a Magnetic Field? A Magnetic Field is a region where magnetic materials (like iron & steel) and also wires carrying currents experience a force acting on them No Messing Resources c This Is the Magnetic Field Around a Bar Magnet As a diagram Underwater No Messing Resources c Iron Filings or Compasses Can Be Used to Show the Lines of Magnetic Field The closer the field lines - the greater the magnetic force No Messing Resources c This Is the Magnetic Field Generated by a Solenoid Can you see the similarity of the field pattern with a bar magnet? No Messing Resources c The Right Hand Thumb Rule Shows Which Way the Magnetic Field Goes Current Magnetic field No Messing Resources c Where is the North Pole & South Pole Field lines go from the North Pole to the South Pole S N No Messing Resources c If you look directly into one end of a solenoid, the direction of current flow tells you whether it’s the North Pole or South Pole you’re looking at No Messing Resources c What does the magnetic field look like around 2 bar magnets? N S N N No Messing Resources c What Does a Magnetic Field Look Like on a Horse Shoe Shaped Magnet? No Messing Resources c Explain What Happens Here. Draw the magnets and the field patterns associated with them No Messing Resources c Return to menu Electromagnets No Messing Resources c Electromagnets An electromagnet is just a coil of wire with an iron core. It can be switched on and off when wished No Messing Resources c These Are All Electromagnets They all have • a DC power supply • a soft iron core (e.g a nail) and • a coil No Messing Resources c Electromagnets The strength of an electromagnet depends on 3 factors: • The size of the current • The number of turns on the coil • What the Core is made of No Messing Resources c What Are The Uses Of Electromagnets? 1) Electromagnets can be switched on & off they can therefore be used to pick up (and put down) scrap iron and steel No Messing Resources c 2) The Electric Bell •When the switch is closed the electromagnet is turned on • This pulls the iron arm to the right and sounds the bell • At the same time the contact is broken which immediately turns off the electromagnets and the •The arm swings back.… No Messing Resources c 3) Circuit breakers Soft Iron Coil Pivot Current In Contact Current Out If the current becomes too high the electromagnet attracts the soft iron. This will break the circuit. Circuit breakers have two main advantages over fuses: they work quicker and can easily be reset No Messing Resources c 4) This is the ‘Maglev’ Train It is levitated and pushed along silently and smoothly by electromagnets No Messing Resources c 5) The Loudspeaker Permanent magnet Coil Current Cone Vibrates AC electrical signals from the amplifier are sent to the coil making the coil move over the permanent magnet. These movements make the cardboard cone vibrate and generate the sound No Messing Resources c Return to menu Generating Electricity No Messing Resources c Generating Electricity We can generate electricity through Electromagnetic Induction……… Electromagnetic Induction: The Creation of a Voltage (and maybe a Current) in a wire which is experiencing a Change in Magnetic Field No Messing Resources c Electromagnetic Induction N The ‘field lines’ have to be cut. No current is produced if the magnet is not moving! If You push a magnet into a coil the electrons in the coil are also given a push. This makes an ‘induced voltage’ No Messing Resources c Electromagnetic Induction Notice the needle moves in the opposite direction N If You pull a magnet out of the coil the electrons in the coil are once again given a push. This makes an ‘induced voltage’ in the opposite direction No Messing Resources c How Can You Increase the Size of the Induced Current? 1. Move the Magnet Faster 2. Use a Stronger (not bigger!) Magnet 3. Put more Turns on the Coil No Messing Resources c We can use a magnet, coil and movement to generate electricity with this device Will it make AC or DC Current? No Messing Resources c This is a Generator You will have heard them near road works generating the electricity to make the traffic lights and machines work No Messing Resources c AC Generator Induced current can be increased in 4 ways: 1) Increasing the speed of movement 2) Increasing the magnetic field strength 3) Increasing the number of turns on the coil 4) Increasing the area of the coil No Messing Resources c Bikes often have Dynamos to make electricity to light a bulb Dynamos are slightly different from generators as they rotate the magnet No Messing Resources c If the Needle on the Centre Spot Galvanometer Moves Right 1 Division When the Magnet Is Placed Into the Coil, What Happens When…. 1) The magnet is pulled out at equal speed? 2) The magnet is put in faster? 3) The magnet is left motionless inside No Messing Resources c the coil? 1) Explain what happens when the handle turns at a constant rate Use the Key Words in your answer: Magnet, coil, flux, a.c, bulb shines, movement 2) Give 3 methods to increase the brightness of the bulb No Messing Resources c Return to menu The Electric Motor No Messing Resources c The Electric Motor The Electric Motor is designed to change electrical energy into movement energy. It Can do this because……. Anything carrying an electric current in a magnetic field experiences a force No Messing Resources c Lots of Machines Need Motors to Work The motors we use in science may look like this No Messing Resources c Force The Simple Electric Motor S Split Ring Commutator N Force No Messing Resources c The Simple Electric Motor The 4 factors which speed it up are:• More Current • More Turns on the Coil • A Stronger Magnetic Field • A Soft Iron Core in the Coil No Messing Resources c The Simple Electric Motor – How Does It Work? Because there is a current in a magnetic field there is a force produced. The force acts on the two side arms of the coil and causes it to rotate on the spindle.The split ring commutator is a clever way of swapping the contacts every half turn to keep the motor rotating in the same direction No Messing Resources c How Can We Reverse the Direction of the Motor? 1. Swap the polarity of the D.C. Supply 2. Swap the Magnetic Poles over No Messing Resources c Fleming’s Left Hand Rule Tells You Which Way the Force Acts thuMb Motion First finger Field seCond finger Current Return to Menu No Messing Resources c Transformers No Messing Resources c Transformers Transformers transform (change) the Voltage Transformers only work on AC because there is constantly changing flux No Messing Resources c Step Up & Step Down Primary Coil Secondary Coil Primary Coil Secondary Coil Step Up Transformer Step Down Transformer More turns on the Secondary Coil More turns on the Primary Coil No Messing Resources c Some Transformers Look Like This….. …..you might have heard their characteristic ‘hum’ No Messing Resources c The Transformer Equation Primary voltage = Secondary voltage Number of turns on Primary Number of turns on Secondary The ratio of the turns on the coils equals the ratio of their voltages No Messing Resources c Complete the table Primary Voltage Secondary No. of No. of Step Up Voltage Turns on Turns on or Step Primary Secondary Down? 12V 36V 100 ? ? 600V 300V 20 ? ? 20,000V 50,000V 1,000 ? ? 23V 230V 150 ? ? No Messing Resources c Return to Menu Power Stations No Messing Resources c What is a power station? Power Stations are places where electrical energy is made. Electrical Energy is a convenient form of energy to use in our homes. No Messing Resources c Fossil Fuel Power Stations Can Generate A Lot Of Pollution In the form of carbon dioxide, sulphur dioxide and smoke No Messing Resources c The sulphur dioxide can lead to the production of acid rain It can damage leaves And whole forests No Messing Resources c Return to Menu The National Grid No Messing Resources c What is the National Grid? When electricity is generated in the power station it is transported to us by the National Grid It is a network of pylons and cables that covers the whole country No Messing Resources c The National Grid Power Station 25,000V Step-down Transformer Step-up Transformer 400,000V No Messing Resources c Homes 230V Why Do We Step Up the Voltage? Transmission cables can be hundreds of kilometres long. This means that energy is wasted because of the heating effect of the current. By using a transformer to increase the voltage, the current is reduced, so thinner, lighter & cheaper cables can be used No Messing Resources c Resistance & Power Loss When a current flows through a conductor it has a heating effect so power is wasted. The power loss can be calculated like this…… Power Loss = Current2 X Resistance Power Loss is reduced significantly if the current is reduced No Messing Resources c Return to Menu Related Websites No Messing Resources c Electrical circuits http://www.miamisci.org/af/sln/frankenstein/safety. html - Interactive ‘clickable’ diagram about electrical safety. http://www.bbc.co.uk/apps/ifl/schools/gigaquiz?path =ks3bitesize/elecmag1tb &infile=elecmag1tb and http://www.bbc.co.uk/apps/ifl/schools/gigaquiz?path =ks3bitesize/elecmag2tb&infile=elecmag2tb Activities about electrical circuits, http://www.crocodile-clips.com/m6_4.htm - Download free software called crocodile-clips, which allows you to create virtual circuits. (Has worksheets also) No Messing Resources c http://www.brainpop.com/science/electricity/elect ricity/ - Electricity in general rather than circuits specifically - excellent for putting it all in context (movie and quiz). Pages from How Stuff Works explaining basic electrical items: http://home.howstuffworks.com/toaster.htm (toaster) http://home.howstuffworks.com/burglar-alarm.htm (burglar alarm) http://home.howstuffworks.com/doorbell.htm (doorbell) http://home.howstuffworks.com/dimmerswitch.htm (dimmer switch) No Messing Resources c Energy and electricity http://www.article19.com/shockwave/ph.htm - This interactive house lets you turn on household electrical items and see the immediate effect on your electric bill. http://www.miamisci.org/af/sln/frankenstein/static. html - Info on static electricity and how to generate it and http://www.bbc.co.uk/schools/gcsebitesize/physics/ electricity/ electricchargeandcurrentrev4.shtml some great images/animations from BBC Bitesize. No Messing Resources c http://www.brainpop.com/science/electricity/ electricity/ (electricity) http://www.brainpop.com/science/energy/ (all BrainPOP energy-related topics) http://www.phy.hr/~dpaar/fizicari/xfaraday.ht ml - Biography of Michael Faraday (known for his electricity and magnetism experiments) No Messing Resources c Magnets and electromagnets http://www.brainpop.com/science/forces/magnetism/ - movie and quiz on magnetism http://www.brainpop.com/science/forces/magneticpo les/ - on magnetic poles. http://education.magnet.fsu.edu/maglabalpha/html/e xpeditions/ whatmagnet.html - text-based information on magnets and http://www.phys.lsu.edu/dept/opps/key_ideas_about _magnets.htm lots of key facts about magnets (good for research). No Messing Resources c http://science.howstuffworks.com/electromagnet.htm - Electromagnets, from How Stuff Works (includes useful animation) and http://electronics.howstuffworks.com/speaker.htm how speakers work (may be handy for research – speakers contain electromagnets). http://www.bbc.co.uk/apps/ifl/schools/gigaquiz?path= ks3bitesize/elecmag2tb &infile=elecmag2tb - test on electromagnets (and electrical circuits) from BBC Bitesize. No Messing Resources c http://www.zephyrus.co.uk/whataremagnets.html Good, simple explanation of what a magnet is in terms of lots of aligned polar molecules. http://www.units.muohio.edu/dragonfly/find/find/ compass.htmlx - info about compasses and how to make your own compass. No Messing Resources c Return to Menu