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Chapter 1: Basic Electricity
Electricity A manufactured product; Electric charge An amount of electricity that is held in or carried by something Two types of electricity Static (at rest) and Electric (moving) Static Electrons are at rest Electric Movement of charge Electron Negatively charged particle Proton Positively charged particle Direct current Flows in one direction Alternating current Flows back and forth Explain how electricity is produced Electricity is generated by using any kind of energy to move the copper armature inside the generator to produce electricity. Electricity is a manufactured product. Electric power is manufactured from a rotating machine that we call an electrical generator. After it is generated, (manufactured) it is then delivered through copper wires to where it is utilized. Electricity is associated with electric charge, a property of certain elementary particles such as electrons and protons, two of the basic particles that make up the atoms of all ordinary matter. There are two types of electricity: static (stationary) and electric (moving). Static electricity can be produced by rubbing together two objects made of different materials. An electric current is a movement of charge. Electron is a negatively charged particle found in an atom. Proton is an elementary particle that carries a positive electric charge. Direct Current is a current that flows in one direction. In DC circuit, electrons emerge from the negative pole and moves towards the positive pole. Alternating Current is a current that flows back and forth, reversing direction again and again. AC electricity is a type of electricity commonly used in homes and business throughout the world. How to Produce Electricity: Electricity is generated by using any kind of energy to move the copper armature inside the generator to produce electricity. The source of energy doesn't matter; it just has to be strong enough to turn the generator. Dynamos and Generators: A key part of most electric power plants is the generator, a device that turns rotary motion into electricity. Inside the generator, coils of copper wire spin inside a strong magnetic field. As the coils move, the magnetic field creates the flow of alternating current (AC) electricity inside the wire. The dynamo, a "cousin" of the generator, works in much the same way; however, it produces direct current (DC). Electric from Steam : A steam power plant (or generator) produces electricity by burning fuels. Steam generated from the process is fed into a turbine. The copper armature (wire) in the generator turns with the rotation of the turbine, producing an electric current. Six Different Ways Electricity Is Produced
- Chemical Light
- Friction Magnetism
- Heat Pressure Different ways to make electricity
- Dynamos and Generators, Electric from Steam
- Hydroelectric Power: Falling Water, Windmills: Energy from Wind
- Solar Power: Energy from Sunshine.
Hydroelectric Power: Electricity that is generated from water is called hydroelectricity. Falling water rotate the blades of a hydroelectric turbine, which in turn moves the copper armature inside the electric generator to produce electricity. Windmills: A wind power plant rotates the blades of a turbine, which move the copper armature (that lies within the generator) to generate electricity. Solar Power: Photovoltaic cells utilize the energy of the sunlight to produce electricity. Direct current (DC) is generated from stationary solar panels (which are made up of photovoltaic cells) and is commonly used for local applications.
Sources of Energy
Solar Energy harvests the energy of the sun through using collector panels. Wind Energy using turbines to take available wind as the power to turn, the turbine of the generator Geothermal Energy the energy that is produced from beneath the earth. Hydrogen Energy it is available with water (H2O) and is most common element available on earth. Wave Energy it can be harnessed along coastal regions. It is produced from the waves that are produced in the oceans. Tidal Energy uses rise and fall of tides to convert kinetic energy into electrical energy. Hydroelectric Energy harnesses the power of water in motion—such as water flowing over a waterfall—to generate electricity. Biomass Energy produced from organic material and is commonly used throughout the world. Nuclear Power the energy is created through a specific nuclear reaction Fossil Fuels (Coal, Oil, Natural Gas) provide the power for most of the world, primarily using coal and oil.
Sources of Electric Current
Generators use mechanical energy, such as water pouring through a dam or the motion of a turbine driven by steam, to produce electricity. Electrolytic cells use chemical energy to produce electricity. Chemical reactions within an electrolytic cell produce a potential difference between cell’s terminals. Fuel cells produce electricity through chemical reactions. Unlike electrolytic cells, however, fuel cells do not store chemicals and therefore must be constantly refilled. Electricity produced directly by heating is called thermoelectricity. Some substances emit electrons when they are struck by light. Electricity produced in this way is called photoelectricity. When pressure is applied to certain crystals, a potential difference develops across them. Electricity thus produces is called piezoelectricity.
Chapter 2: Conductors & Insulators
A phenomenon known as superconductivity is observed when certain substances are cooled to a point near absolute zero, at which point their conductivity becomes almost infinite. Electron – (noun Physics) a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids. Conductor – (Physics) a material or device that conducts or transmits heat, electricity, or sound, especially when regarded in terms of its capacity to do this. Insulator – (noun) a substance which does not readily allow the passage of heat or sound. A substance or device which does not readily conduct electricity. Electric Circuit – a path for transmitting electric current. Semiconductor – (noun) a solid substance that has a conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects. Dielectric – (adjective) having the property of transmitting electric without conduction; insulating. (noun) a medium or substance that transmits electric force without conduction, an insulator.
IC is a special component which is fabricated with thousands of transistors, resistors, diodes, and other
electronic components on a tiny silicon chip.
Transistors
A three-terminal device in which a voltage applied to one of the terminals (base) can control current that flows across the other terminals (collector and emitter).
Induction
Induction is the creation of an electric current in a conductor moving across a magnetic field.
Rectification
The process of converting an alternating current (AC) to direct current (DC)
Rectifier
A device which permits current to pass in only one direction, effectively blocking its flow in the other direction.
LCD (Liquid Crystal Display)
LCD is a flat display technology, which is mostly used in applications like computer monitors, cellphone display, calculators, etc.
CRT (Cathode Ray Tube)
Mostly used in televisions and computer screens that works on the movement of an electron beam back and forth on the back of the screen.
Batteries
It converts chemical energy into electrical energy through electrochemical discharge reactions. Primary Cell – not rechargeable Secondary Cell – rechargeable
Chapter 4: Instrumentation
Voltmeter – measures the voltage across two points of an electric circuit. DC and AC Voltmeter Ammeter – measures the current across two points of an electric circuit. DC and AC Ammeter Ohmmeter – measure the value of resistance across two points of an electric circuit. Multimeter – (Electronic Multimeter or Voltage Ohm Meter (VOM)) instrument used to measure voltages, currents, and resistance. Voltage (Volt) – electric pressure that pushes charged electrons (current) through a conducting loop. Current (Ampere) – flow of electric charge Resistance (Ohm) – blocks or limits the flow of the current Inductance (Henry) – stabilizes the current
Chapter 5:
Carbon Composition Resistor Made of fine carbon particles mixed with a binder Thermistor Resistance is dependent on temperature Wire Wound Resistor Restricts current flow Metal Film Resistor Has a thin metal layer as resistive element Carbon Film Resistor Constructed out of ceramic carrier with thin pure carbon film Variable Resistor Resistance value can be adjusted
Schematic Diagram
Chapter 6: Transformer
Transformer is an electrical device consisting of one coil of wire placed in close proximity to one or more other coils, used to couple two or more alternating-current (AC) circuits together by employing the induction between the coils. A Transformer basically is a very simple static (or stationary) electro-magnetic passive electrical device that works on the principle of Faraday’s Law of induction by converting electrical energy from one value Varistor Electrical resistance that varies with the applied voltage Light Dependent Resistor Resistance changes with the light intensity
