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Practical electricity - Coggle Diagram

- - - - the heating element in kettles, irons, ovens and heater use nichrome wires due to its high resistivity and ability to withstand high temperatures (high melting point). When an electric current passes through the heating element, thermal energy is generated
    - - The filament in filament bulbs is made from Tungsten due to its high resistivity and melting point (ability to withstand high temperature). The filament is thin, giving it higher resistance than the rest of the circuit (R=pl/A). Thus, when an electrical current passes through the filament, it gets extremely hot (2500 degrees) and generates light energy
  - - - Renewable energy refers to energy that comes from natural sources that can be replensihed naturally
      - Solar power
        
        solar energy has high efficiency when there is daylight and minimal cloud cover. however, despite being a cleaner energy source, the cost of installation of solar panels are very high and most people would choose fuel which is free. And it requires a large area to be cleared for installation
      - Hydroelectric power
        
        Hydroelectric power is the most efficient energy source. However, despite being a cleaner energy source, the cost of construction and maintenance of dams and power plants are high, and the process of construction can disrupt ecosystems,
      - Wind power
        
        Wind power efficiency depends on wind speed and direction. it is a cleaner form of energy with falling cost due to technological improvements. however, it requires a large open area and can cause possible noise pollution.
    - - Non-renewable energy refers to energy that comes from natural sources but cannot be replenished at a sustainable rate
      - Nuclear power
        
        Although nuclear power has high efficiency, there is an additional cost incurred from the disposal of radioactive waste, which can contaminate water from surface or groundwater sources
      - Fossil fuels
        
        fossil fuel plants are well established in many countries, however, there is a rising cost due to declining supplies. furthermore, burning fossil fuels can cause air pollution and the mining for fossil fuels can disrupt ecosystems
- - - - Live wire is the wire connected to a high alternating voltage and delivers an alternating current
    - - Neutral wire completes the circuit and provides a returning path back to the supply and is at 0V
  - - - Shirt circuits are formed due to damaged insulation that causes the live and neutral wire to come into contact with each other, bypassing the resistor and hence causing a large current to flow in the wires and a fire hazard
    - - a thin wire has a higher resistance than a thicker wire. if a high power appliance is fitted with a thin wire, it will draw a large normal operating current to flow through the thin wire. this produces a large amount of heat and power loss as heat is given by RI^2. Hence, this causes overheating and leads to a fire
    - - Appliances plugged into an adapter are connected in parallel. If too many appliances are plugged in and used at the same time, it will draw a large power to flow through the cables from the main supply. Thus, causing an excessively large current to flow through the wires and thus causing overheating and a fire.
  - - - Water in contact with exposed electrical wires can cause an electric shock as water provides a conducting path for current. Thus, electrical appliances must always be handled with dry hands and kept in dry places, especially since the resistance of the human skin when its dry as compared to when its wet is 100000 ohms and 1000 ohms respectively.
    - - Insulating materials can become damaged with time and use, the bending and twisting can also cause the insulating material to crack and break, exposing the wires. exposed live wire can case electric shocks to the user should he make a good connection with the Earth