electrical circuits

• conventional current - flows from positive terminal to negative terminal
• circuit is a closed loop that contains a power source
• current ( I ) - a measure of the flow of electrons around a circuit. Measured in Amps
• Potential difference ( V ) - the force dividing the flow of electrons which is provided by the cell/battery. Measure in Volts.
• resistance ( R ) - everything that opposes the flow of electrons. Measured in ohms
• v = IR
• fixed resistor

  
• filament lamp

  
• diode graph

  
• for fixed resistors and wires, increasing the temperature increases the resistance
• charge - measure of the total current that flowed within a certain period of time
• charge = current x time
• Q = i x t
• components

  
• series circuit

  • current is same everywhere
  • P.D is shared across all components
  • total resistance is equal to the sum of an individual resistance of each component
• series circuit, components with a greater resistance will always have a higher share of the voltage
• parallel circuit

  • potential difference is the same at each component
  • current is shared across all components
  • more components added in parallel decreases the resistance
• parallel circuit loops that have a greater resistance take a lower share of the current
• energy formula

  • energy = power x time
  • energy = voltage x current x time
  • energy = charge x voltage
• power formula

  • power = current x voltage
  • power = current^2 x resistance