Electronics Studies

• Electricity


  1. Energy caused by the movement of electrons

  2. Electric current is the amount of electrons flowing from one place to another in a given time. Current is measured by an Ammeter

  3. Voltage is measured between two points. It is the driving force that causes electric current to flow. Voltage can be compared to the height of the hill causing the water flow. Voltage is measured by a Voltmeter

  4. Resistance is how easy it is for electric current to flow through a material. Resistance could be compared to a river full of bends and obstacles. Current = Voltage divided by Resistance. For the same voltage, the lower the resistance, the higher the current

  5. A conductor has low resistance to current. It requires very little voltage to get lots of current flowing through a conductor. Metals are good conductors

  6. An insulator has high resistance to current. Even large voltages will still not get much current flowing in insulators. Plastics and ceramics are good insulators

  7. Semiconductors have a medium resistance to current. The most well-known semiconductor is silicon, which is used to make devices such as transistors, diodes, and integrated circuits

  8. Power is the amount of electrical energy transferred per second. It can be calculated by multiplying voltage by current
• Capacitor Symbol

  
• LED symbol

  
• Resistor Symbol

  
• Transistor Symbol

  A) Collector

  B) Base

  C) Emitter

  
• Push to break(PTB) symbol

  
• Push to make(PTM) symbol

  
• Fuse Symbol

  
• Double Pole Double Throw Symbol

  
• Single pole, Single throw (SPST) toggle switch

  
• Power supply converts high voltage AC to low voltage DC
• What do Batteries do

  Supply a few Volts DC
• Solar Cells convert light energy into electrical energy, they generate low DC voltage
• What do Solar Cells do

  Convert light energy into electrical energy
• Fuse is a safety device that melts when the current is too high and stops the flow of electricity
• What does a Fuse do

  When too much current flows, it blows and stops the current
• A SPST toggle switch is a on/off switch that is operated by a lever. SPST means single pole, single throw which means it has 2 connections. One position of the switch closes the circuit and the other breaks the circuit.
• What is a SPST Toggle Switch

  A single pole single throw toggle switch is an on and off switch that is operated by a lever, it has 2 connections, One closes the circuit and the other opens the circuit.
• Push button switches contains an internal spring and only stays pushed in while you keep your finger on it. Push to make(PTM) closes the circuit when pushed and Push to break(PTB) opens the circuit when pushed
• A Double Pole Double Throw(DPDT) switch is a switch that can be used to control a circuit with two separate loads and it is comprised of two separate switches operated at the same time. Each switch has one input and 2 outputs. A DPDT switch has 6 connections
• Resistors limit the current flowing through them. Fixed resistors are made in fixed values which can be read using the coloured bands. Variable Resistor is used to adjust the resistance of a circuit via a knob.
• Diode only allows current to flow in one direction. Diodes are polarised components and must be connected right way around to work.
• Diode Symbol

  
• Transistor is used to amplify an electrical signal. The current goes in to the base which becomes a larger current flowing from the collector to emitter. Transistor can be used as an electronic switch.
• Capacitors store small amounts of electrical charge(electrons). Capacitors are used in timer circuits because they take little time to charge up. Some Capacitors are polarised, they have a positive connection and negative connection. They only work when put the right way
• Polarised Capacitor Symbol


  Electrolytic Capacitor

  
• Variable Resistor Symbol


  Potentiometer

  
• Variable Resistor Symbol 


  Potentiometer

  
• Variable Resistor Symbol


  Potentiometer

  
• Battery Symbol

  
• Battery Symbol

  
• Bulb emits light and heat when current passes through it. it is not energy efficient.

  
• • LED(Light Emitting Diode)
  • Energy Efficient
  • Works with Low DC Voltage
  • Polarised(only works one around)
  • Used as Power On indicators Commonly

  
• • Buzzer emits a fixed sound when activated and is the output for sound signal.

  
• In Alternating Current(AC) electricity, the voltage and current continually reverse direction many times a second. Mains electricity in the home is AC is 220 Volts AC. High Voltage AC is powerful enough to drive large motors and loads. High voltage AC loses less energy when transported over long distances.
• Alternating Current Electricity Symbol

  
• Direct Current(DC) electricity, the voltage remains constant and the current flows in one direction only. Low voltage DC is used in all electronic devices and it is safe to touch.
• Direct Current Electricity Symbol

  
• Voltage is measured in Volts(V) with a Voltmeter. Resistance is measured in Ohms. Current is measured is Amps(A) with an Ammeter. Power is measured in Watts(W). Power is calculated by multiplying voltage by current.
• Ohm's law is Current equals voltage divided by Resistance