lesson 1-7.pdf

 What Makes It Work? Look at these pictures. Think about what all the items have in common. How do they all work? ELECTRICITY CREATIVE TECHNOLOGY STE 9  What Makes It Work? Look at these pictures. Think about what all the items have in co...

 What Makes It Work? Look at these pictures. Think about what all the items have in common. How do they all work? ELECTRICITY CREATIVE TECHNOLOGY STE 9  What Makes It Work? Look at these pictures. Think about what all the items have in common. How do they all work?  What is Electricity? When we refer to , what we usually mean is , which is the of occurs naturally. Some examples include: is produced in living things, such as electric eels  What is Electricity? Electricity powers many of the things we use everyday - televisions, phones, computers, lights and microwaves.  What is Electricity? There are two types of electrical current that we use to power appliances: which is an which generate a  ACTIVITY #1 Group yourselves into five. Every group must illustrate a simple scenario where electricity does not exist. You are given 10 minutes to illustrate and present your ideas in the class. FOSSIL FUELS  Boiler Turbine Generator Grid FUEL Chemical Heat Kinetic Electrical energy energy energy energy Facts The fossil fuels are coal, oil and natural gas. They are fuels because they release heat energy when they are burned. Fossil Fuels were formed from the remains of living organisms millions of years ago. About three-quarters of the electricity generated in the UK comes from power stations fuelled by fossil fuels.  Advantages A major advantage of fossil fuels is their capacity to generate huge amounts of electricity in just a single location. Fossil fuels are very easy to find. When coal is used in power plants, they are very cost effective. Coal is also in abundant supply. Transporting oil and gas to the power stations can be made through the use of pipes making it an easy task. Power plants that utilize gas are very efficient. Power stations that make use of fossil fuel can be constructed in almost any location. This is possible as long as large quantities of fuel can be easily brought to the power plants.  Disadvantages Fossil fuels are non-renewable energy resources. They are limited and they will eventually run out one day. Fossil fuels release carbon dioxide when they burn, which adds to the greenhouse effect and increases global warming. Of the three fossil fuels, for a given amount of energy released, coal produces the most carbon dioxide and natural gas produces the least. Coal and oil release sulfur dioxide gas when they are burnt, this then causes breathing problems for living creatures and contributes to acid rain. NUCLEAR POWER STATIONS Fuel rods of uranium and plutonium Facts The main nuclear fuels are uranium and plutonium, both of which are radioactive metals. Nuclear fuels are not burned to release energy. Instead, heat is released from changes in the nucleus. Just as with power stations burning fossil fuels, the heat energy is used to boil water. The kinetic energy in the expanding steam spins turbines, which drive generators to produce electricity Advantages Unlike fossil fuels, nuclear fuels do not produce carbon dioxide. Disadvantages Like fossil fuels, nuclear fuels are non-renewable energy resources. If there is an accident, large amounts of radioactive material could be released into the environment. Nuclear waste remains radioactive and is hazardous to health for thousands of years. It must be stored safely. BIOFUELS Facts Biofuels are fuels produced from plant material. For example, bioethanol is produced from plant sugar and biodiesel is produced from plant oils. Unlike fossil fuels, biofuels are renewable resources. In addition, their use may lead to an overall reduction in emissions of carbon dioxide because the growing plants absorb carbon dioxide from the atmosphere.  Advantages Are cheaper than fossil fuels. Many governments are now offering tax incentives to buy greener cars that run on biofuels (ethanol being one example). Are considered ‘carbon neutral’ by some people. Reduces carbon emissions by 50-60%. Reduce dependence on foreign oils. Oil fluctuates in price rapidly, so changing to biofuels will help buffer against the change. Emit less particulate pollution than other fuels, especially diesel. Are renewable sources of energy as you can just keep producing more. Ethanol is very inexpensive to produce. Can help prevent engine knocking. Disadvantages Setting aside land to grow biofuels means that there is less land to grow food. It is also possible that food prices will rise as a result. More land must be set aside to make biofuels. Natural habitats (flora and fauna) may be lost as a result. There are better solutions- such as using hydrogen fuel cells. Not many gas stations have biofuels available at the moment. This discourages people from buying cars that are not reliant only on gas. Burning corn may release high concentrations of nitrous oxide into the air, which is a greenhouse gas. WIND Facts Wind turbines (modern windmills) turn wind energy into electricity. The wind is produced as a result of giant convection currents in the Earth's atmosphere, which are driven by heat energy from the sun. This means that the kinetic energy in wind is a renewable energy resource: as long as the sun exists, the wind will too. Wind turbines have huge blades mounted on a tall tower. The blades are connected to a nacelle or housing that contains gears linked to a generator. As the wind blows, it transfers some of its kinetic energy to the blades, which turn and drive the generator. Several wind turbines may be grouped together in windy locations to form wind farms. Advantages Wind is free, wind farms need no fuel. Produces no waste or greenhouse gases. The land beneath can usually still be used for farming. Wind farms can be tourist attractions. A good method of supplying energy to remote areas. Wind power is renewable. Winds will keep on blowing, it makes sense to use them. Disadvantages The wind is not always predictable - some days have no wind. Suitable areas for wind farms are often near the coast, where land is expensive. Some people feel that covering the landscape with these towers is unsightly. Can kill birds - migrating flocks tend to like strong winds. However, this is rare, and we tend not to build wind farms on migratory routes anyway. Can affect television reception if you live nearby. Can be noisy. Wind generators have a reputation for making a constant, low, "swishing" noise day and night, which can annoy people. WAVE Facts The water in the sea rises and falls because of waves on the surface. Wave machines use the kinetic energy in this movement to drive electricity generators. Advantages Wave power is a renewable Energy Source. Wave Energy Is a Clean Fuel. Wave Energy is Environmentally Friendly - it doesn't destroy the environment. There is plenty of it. Tides/Waves are always predictable. You can always produce a significant amount of energy. You don't need fuel so it doesn't cost that much. Waves are free and will not run out so the cost is in building the power station. Disadvantages It can cost a lot of money and requires further research. If the whole tidal/wave energy scheme does get popular real estate will be losing money for beach front houses since they will be using the beaches for the tidal/wind farms. It depends where you put it for the costs so not much good financially May interfere with mooring and anchorage lines commercial and sport fishing. Waves can be big or small so you may not always be able to generate electricity. You need to find a way of transporting the electricity from the sea onto the land. HYDROELECTRIC Facts To make electricity this way, the water is held in a reservoir, behind the dam. The water close to the control gates is where the intake is, and when the control gates open, the water rushes through the penstock and turns the turbine. After the water does so, it goes through the outflow into the river. The turbine spins the generator, and the electricity goes to the transformer in the powerhouse. Then the transformer transforms the electricity into a usable form, and the electricity travels through the power lines and goes to homes and businesses. Advantages Once a dam is constructed, electricity can be produced at a constant rate. If electricity is not needed, the sluice gates can be shut, stopping electricity generation. Dams are designed to last many decades and so can contribute to the generation of electricity for many years. The lake that forms behind the dam can be used for water sports and leisure / pleasure activities. Often large dams become tourist attractions in their own right. The build up of water in the lake means that energy can be stored until needed, when the water is released to produce electricity. When in use, electricity produced by dam systems do not produce green house gases. They do not pollute the atmosphere.  Disadvantages Dams are extremely expensive to build and must be built to a very high standard. The flooding of large areas of land means that the natural environment is destroyed. People living in villages and towns that are in the valley to be flooded, must move out. The building of large dams can cause serious geological damage. Although modern planning and design of dams is good, in the past old dams have been known to be breached. This has led to deaths and flooding. Dams built blocking the progress of a river in one country usually means that the water supply from the same river in the following country is out of their control. Building a large dam alters the natural water table level. SOLAR  Facts Solar cells are devices that convert light energy directly into electrical energy. Larger arrays of solar cells are used to power road signs in remote areas. Solar panels do not generate electricity, but rather they heat up water. They are often located on the roofs of buildings where they can receive heat energy from the sun. Cold water is pumped up to the solar panel, there it heats up and is transferred to a storage tank. A pump pushes cold water from the storage tank through pipes in the solar panel. The water is heated by heat energy from the sun and returns to the tank. In some systems, a conventional boiler may be used to increase the temperature of the water. Advantages Solar energy is a renewable energy resource There are no fuel costs. No harmful polluting gases are produced. Disadvantages Solar cells are expensive and inefficient, so the cost of their electricity is high. Solar panels may only produce very hot water in very sunny climates, and in cooler areas may need to be supplemented with a conventional boiler. Although warm water can be produced even on cloudy days, neither solar cells nor solar panels work at night. GEOTHERMAL  Grid turbines 7Km Facts Several types of rock contain radioactive substances such as uranium and plutonium. Radioactive decay of these substances releases heat energy, which warms up the rocks. In volcanic areas, the rocks may heat water so that it rises to the surface naturally as hot water and steam. Here the steam can be used to drive turbines and electricity generators. This type of geothermal power station exists in places such as Iceland, California and Italy.... Hot rocks In some places, the rocks are hot, but no hot water or steam rises to the surface. In this situation, deep wells can be drilled down to the hot rocks and cold water pumped down. The water runs through fractures in the rocks and is heated up. It returns to the surface as hot water and steam, where its energy can be used to drive turbines and electricity generators Advantages Geothermal energy is a renewable energy resource and there are no fuel costs. No harmful polluting gases are produced. Disadvantages Most parts of the world do not have suitable areas where geothermal energy can be exploited. Conductors and Insulators Conductors are made of materials that electricity can flow through easily. These materials are made up of atoms whose electrons can move away freely.  Metals in general are the best conductors of electricity. The atoms of metal elements are characterized by the presence of electrons in the outer shell of an atom that are free to move about. It is these ‘free electrons’ that allow metals to conduct electric current. Many metals like copper, iron, silver etc. are good conductors of electricity.  Silver is the most conductive metal, however it is very expensive and hence is rarely used. All the electric wires are generally made from copper. Some examples of conductors are: COPPER ALUMINUM PLATINUM GOLD SILVER WATER PEOPLE AND ANIMALS TREES Superconductor: A superconductor is a material that is a perfect conductor. Superconductors are usually a mix of two or more metals. Superconductor: However these are not superconductors at room temperature. They show zero resistance to electric flow at very low temperature usually below -200 degrees celsius. Insulators are materials opposite of conductors. The atoms are not easily freed and are stable, preventing or blocking the flow of electricity.  In insulators the outer electrons are tightly held together, which prevents them from moving. When the movement of electrons is restricted, no current can flow through them. Non-metals such as glass, wood, plastic are excellent insulators as they have high resistance to the flow of electric current.  This is true for normal voltage but increase in voltage may conduct some passage for electricity. Insulating materials like plastic, wood etc are used to cover materials that carry electricity. Some examples of insulators are: GLASS PORCELAIM PLASTIC RUBBER Electricity will always take the shortest path to the ground. Your body is 60% water and that makes you a good conductor of electricity. If a power line has fallen on a tree and you touch the tree you become the path or conductor to the ground and could get electrocuted.  It must be noted that all conductive material do not have the same conductivity and similarly not all insulators have the same level of insulation. Conductivity and insulation also depends on physical dimension of the material.  Two wire of same length but with different diameter, the wire with bigger diameter is a better conductor than the wire with lesser diameter. Similarly two wires of same diameter but with different lengths then the wire with shorter length has proved to be a better conductors than the longer wire.  SHORT QUIZ Get 1/4 sheet of paper 1/4 sir? Yes 1/4 1)____ allows most electricity to pass through them. a)Insulators b)Conductors c)Semi-conductors d)None of these 2. ________ move freely in conductors which allow flow of electricity. a. Atoms b. Protons c. Current d. electrons 3. _______ has zero resistance. a)Super-conductors b)Water c)Ice d)Silver 4. Super conductors work only at temperature below ______ o a)-200 F o b) 200 C o c) 200 F o d) -200 C 5. _______ does not allow electricity to pass through them. a)Water b) people c) animals d) Plastic 6. _______ does not allow electricity to pass through them. a)Water b) people c) animals d) Plastic 7. _______ is a perfect conductors. a)insulators b) semiconductors c) Superconductors d) none 8. TRUE or FALSE: Aluminum is cheaper than silver. 9. TRUE or FALSE: Aluminum is a better conductor of electricity compared to copper. 10. TRUE or FALSE: Pure water conducts electricity.  Lesson 4: Parallel and Series Circuits 01 Series Circuit  Series Circuits Only one path for current to flow The current is the same in all parts of the circuit. IT = I1 = I2 = I3… Therefore, the number of coulombs passing through each load is the same. If the circuit is broken at any point, then the current flow stops.  Series Circuits Since the current flows through all loads, electrons lose energy as they pass through each load. The potential difference (voltage) is split between the loads in the circuit. Therefore, VT = V1 + V2 + V3 …  Series Circuit The resistance increases with each load. RT = R1 + R2 + R3 … The power increases with each load PT = P1 + P2 + P3 … 02 Parallel Circuit  Parallel Circuits There is more than one path for the current to flow Current is NOT the same at different points. The current (the electrons) is shared by as many paths as there exist. Current flowing from the energy source equals the sum of all the separate branch currents in the circuits. IT = I1 + I2 + I3 … I, in each path, depends on the size of the resistor. The more resistors, there are in the circuit, the more “pull” for energy and the greater the current.*  Parallel Circuit If any one device is removed, it does not affect the others. Each branch circuit is connected directly across the battery, therefore has the identical potential difference as there is across the battery. VT = V1 = V2 = V3 …  Parallel Circuit Adding resistance in parallel, decreases the total resistance of the circuit. RT = 1/R1 + 1/R2 + 1/R3 … The power is calculated as follows: PT = P1 + P2 + P3 … 03 Electricity in the home Two Types of Current Direct current – electrons always travel in one direction as in batteries and cells. Alternating current – electrons go back and forth rapidly sixty times per second. This allows for efficient distribution of high voltage electricity via transformers that increase (step up) or decrease (step down) the potential difference of power lines as it gets closer to your home or school  Fun Fact Do you know who invented alternating current? Nikola Tesla Electricity in the home If too much current flows through a wire, it overheats which can lead to a fire. Fuses and circuit breakers detect dangerous current overloads. FUSES – a thin wire that melts at a pre-determined current level so as to break the circuit. Must be replaced with a new fuse. CIRCUIT BREAKER – a heat sensitive switch that “trips” off when current overheats the wire. Can be reset by flipping the switch. Electricity in the home In your home, a digital or dial meter reads the electric current used in kilowatt-hours (1 kW h = 1000 watt hours). Measurements WHAT’S A JOULE?? A JOULE (J) is the unit for ENERGY WHAT’S A WATT?? A WATT (W) is the unit for power - a kilowatt (kW) is one thousand watts ( 1.0 kW = 1000 W) POWER POWER MEASURES “HOW FAST” YOU USE ENERGY – THE EQUATION FOR POWER IS Unit of energy THE kWh as a UNIT OF ENERGY ( hint: get “E” by itself in the power equation)  BASIC ELECTRONIC COMPONENTS Creative Tech STE 9 Voltage: Potential refers to the the possibility of doing work. The symbol for potential difference is E (for electromotive force) The practical unit of potential difference is the volt (V) 1 volt is a measure of the amount of work required to move 1C of charge Current: When a charge is forced to move because of a potential difference (voltage) current is produced. In conductors - free electrons can be forced to move with relative ease, since they require little work to be moved. So current is charge in motion. The more electrons in motion the greater the current.  Amperes: Current indicates the intensity of the electricity in motion. The symbol for current is I (for intensity) and is measured in amperes. The definition of current is: I = Q/T Where I is current in amperes, Q is charge in coulombs, and T is time in seconds. Closed Circuits: In applications requiring the use of current, electrical components are arranged in the form of a circuit. A circuit is defined as a path for current flow. Open circuit : current can only exist when there is conduvtive path. In the circuit I= 0, since there is no conductor between points a and b. we reffered to this as an open circuit. Direction of Electron Flow The direction of electron flow in our circuit is from the negative side of the battery, through the load resistance, back to the positive side of the battery. Direction of conventional current The direction of conventional current in our circuit is from the positive side of the battery, through the load resistance, back to the negativeside of the battery. Direct Current: Circuits that are powered by battery sources are termed direct current circuits. It is the flow of charges in just one direction Alternating Current: An alternating voltage source periodically alternates or reverses in polarity. The resulting current, therefore, periodically reverses in direction.  Resistance: Opposition to the flow of current is termed resistance. The fact that a wire can become hot from the flow of current is evidence of resistance. Conductors have very little resistance. Insulators have large amounts of resistance. Resistors A resistor impedes the flow of electricity through a circuit. Resistors have a set value. Since voltage, current and resistance are related through Ohm’s law, resistors are a good way to control voltage and current in your circuit. 10 More on resistors Resistor color codes 1st band = 1st number 2 nd band = 2 nd number 3rd band = # of zeros / multiplier 4 th band = tolerance 11 Color code 12 Units Knowing your units is important! Kilo and Mega are common in resistors Milli, micro, nano and pico can be used in other components K (kilo) =1,000 M (mega) = 1,000,000 M (milli) = 1/1,000 u (micro) = 1/1,000,000 n (nano) = 1/1,000,000,000 (one trillionth) p (pico) = 1/ 1,000,000,000,000 (one quadrillionth) 13 Ohm’s Law The amount of current in a circuit is dependent on its resistance and the applied voltage. Specifically I = V/R If you know any two of the factors V, I, and R you can calculate the third. Current I = V/R Voltage V = IR Resistance R = V/I Power: The unit of electrical power is the watt. Power is how much work is done over time. One watt of power is equal to the work done in one second by one volt moving one coulomb of charge. Since one coulomb a second is an ampere: Power in watts = volts x amperes P=VxI P = I² x R P = V² / R Capacitors A capacitor stores electrical energy. Capacitance is measured in Farads. The small capacitors usually used in electronics are often measured in microfarads and nanofarads. Some capacitors are polarized. Note the different length terminals on one of the capacitors. 16 Polarity of capacitors The shorter terminal goes on the negative side (cathode). 17 Diode A diode is a one way valve (or gate) for electricity. It is a component with an asymmetrical transfer characteristic. A diode has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other direction. Diodes will protect your electronics. 18 Diode circuit protection In an electronic circuit, if the polarity is wrong, you can fry your components. Diodes have a bar on the cathode (negative) side. 19 Light emitting diode (LED) A light emitting diode (LED) is a semiconductor light source. When electricity is passing through the diode, it emits light. 20 Variable resistor / Potentiometer A potentiometer is a variable resistor. As you manually turn a dial, the resistance changes. 21 Transistors A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power. This is our electronic switch! 22 How a transistor works Avoltage or current applied to one pair of the transistor’s terminals changes the current through another pair of terminals. A transistor is composed of semiconductor material with at least three terminals for connection to an external circuit. Transistors have 3pins. For these transistors: Collector Emitter Base 23 Terminology BJT versus FET Bipolar junction transistor. Useful as amplifiers. Collector, Emitter, Base Field-effect transistor. Useful as motor drivers. Source, Drain, Gate MOSFET: Metal-oxide-semiconductor FET NPN (N-channel FET) versus PNP (P-channel FET) NPN versus PNP is how the semiconductors are layered. NPN: Not pointing in PNP: Pointing in permanently 24 Schematic symbols BJTPNP BJTNPN P-channel FET N-channel FET 17 Integrated circuit An integrated circuit (IC) is a set of transistors that is the controller or ‘brain’ of an electronic circuit. An input is received, an output is sent out. Modern microprocessor ICs can have billions of transistors per square inch! 26  Printed Circuit Board Components are attached to a printed circuit board. The ‘front’ side of the board will have printed component information, such as resistor # and resistance, diode type and polarity, etc. Holes go all the way through the board from one side to the other. Through- hole soldering is needed to connect components to the board. 27  Back of Circuit Board The ‘back’ side of the board will have lines indicating connections between components. The lines on the back are similar to wires. Thicker lines denote more current (electrons) moving through. Components connect the lines. 28  BASIC C++ COMMANDS/FUNCTIONS ARDUINO Creative Technology 9 VO ID S E T U P( ) The setup() function is a special function in Arduino sketches (programs) that runs once when the microcontroller (like an Arduino board) starts up or resets. It’s where you set up initial configurations, pin modes, and any other one-time tasks before the main loop begins. VO ID S E T U P( ) Initialization: You typically use setup() to configure pins, serial communication, timers, and other hardware-related settings. Runs Once: Unlike the loop() function (which runs repeatedly), setup() executes only once during startup. VO ID S E T U P( ) void setup() { // Initialize pin modes pinMode(ledPin, OUTPUT); pinMode(buttonPin, INPUT); } VO ID LO O P The loop() function is a crucial part of an Arduino sketch (program). It runs continuously after the setup() function completes. Any code inside loop() executes repeatedly until the microcontroller is powered off or reset. VO ID LO O P Main Execution: You place your primary code logic inside loop(). Continuous Operation: Whatever you write in loop() will keep running indefinitely. VO ID LO O P void loop() { // Your main code here digitalWrite(ledPin, HIGH); // Turns on an LED delay(1000); // Wait for 1 second digitalWrite(ledPin, LOW); // Turns off the LED delay(1000); // Wait again } PINMODE() The pinMode() function is used to configure the mode of a digital pin on an Arduino board. It determines whether the pin will be used for input or output. PINMODE() Syntax: pinMode(pin numbers, mode) pin: The number of the pin you want to configure (e.g., 13, A0, etc.). mode: Either INPUT or OUTPUT. OUTPUT/INPUT OUTPUT is for pins that provide voltage (e.g., to control LEDs, motors, or relays). INPUT is for pins that read external signals (e.g., from buttons, sensors, or switches). OUTPUT/INPUT When a pin is set to “OUTPUT,” it becomes capable of providing voltage (either HIGH or LOW) to external components. In the case of an LED connected to ledPin, setting it to “OUTPUT” allows you to turn the LED on (HIGH voltage) or off (LOW voltage). OUTPUT/INPUT When a pin is set to “OUTPUT,” it becomes capable of providing voltage (either HIGH or LOW) to external components. In the case of an LED connected to ledPin, setting it to “OUTPUT” allows you to turn the LED on (HIGH voltage) or off (LOW voltage). You can use digitalWrite(ledPin, HIGH); to turn the LED on and digitalWrite(ledPin, LOW); to turn it off. OUTPUT/INPUT When a pin is set to “INPUT,” it becomes capable of reading external signals (e.g., from a button, sensor, or switch). In the case of a button connected to buttonPin, setting it to “INPUT” allows you to detect whether the button is pressed (HIGH voltage) or not (LOW voltage). You can use digitalRead(buttonPin) to read the button state (HIGH or LOW). DELAY The delay() function in Arduino programming serves a straightforward purpose: it introduces a pause or delay in the execution of your code. DELAY delay(ms) pauses the program for a specified time in milliseconds (ms). During this delay, the microcontroller (like an Arduino) does nothing except wait. VA R I A B L E I N T A N D C O N S T An int is a data type used to represent whole numbers (both positive and negative) in most programming languages. It stands for “integer.” Commonly used for counting, indexing, and arithmetic operations. VA R I A B L E I N T A N D C O N S T VA R I A B L E I N T A N D C O N S T The const keyword is used to declare a constant—a value that cannot be changed after it’s assigned. Constants are helpful for ensuring that certain values remain fixed throughout your program. VA R I A B L E I N T A N D C O N S T FOR() LOOP A for loop is a control structure that allows you to repeat a block of code a specific number of times. It’s particularly useful when you know in advance how many iterations (repetitions) you need. FOR() LOOP A typical for loop consists of three parts: Initialization: Setting an initial value (usually a counter variable). Condition: Checking if the loop should continue (based on the condition). Update: Modifying the counter variable after each iteration. The loop continues until the condition evaluates to false. FOR() LOOP Syntax: for(initialization, condition, update){ code to be excuted}  FOR() LOOP int i = 1 initializes the counter variable i. i