Electricity

• Static electricity


  The buildup of electric charge on an object
• Static electricity sticks to the balloon
• How static electricity is built up

  1. When two different substances are rubbed together

  2. This creates an imbalance of electric charges
• Opposite electric charges


  Attract each other
• What happens when a charged object touches another object

  1. Both objects become charged

  2. One way to remove static electricity is by grounding, which allows the excess charge to flow into the ground
• Grounding neutralizes the static electricity
• Voltage (V)


  Energy that is carried by electrons
• Current (I)


  How many electrons move past a point in a given time
• Resistance (R)


  The ability of a substance to oppose the flow of electric current
• Resistor


  A device used to control or limit the flow of electric current in a circuit
• Ohm's Law


  V = I x R
• Factors affecting resistance


  • Length of wire
  • Thickness of wire
  • Type of metal in the wire
• Long wire


  High resistance
• Short wire


  Low resistance
• Thin wire


  High resistance
• Thick wire


  Low resistance
• Metals with low resistance


  • Copper
  • Aluminium
  • Silver
  • Gold
• Metals with high resistance

  • Tungsten
  • Nichrome
• Light bulb


  • Tungsten filament
  • Long wire
  • Thin wire
• Voltage is measured in volts (V)
• Current is measured in amperes (A)
• Resistance is measured in ohms (Ω)
• Voltage, current and resistance are related by Ohm's Law: V = I x R
• Parallel circuits have multiple paths for current to flow
• Series circuits have only one path for current to flow
• Current is measured in amperes (A) or amps.
• The current is the flow of electrons around a circuit.
• Loads connected in series

  Increase the total resistance of the circuit
• Power is measured in watts (W).
• To make an object positively charged, you should add electrons to it

  false
• I discharge occurs when two neutral objects are brought together


  False
• Electrical resistance is the

  opposition to electrical current


  true
• A load produces electrical energy to do something useful


  false
• Dividing the current by potential difference of a load, will give you the resistance


  False
• The total resistance of a circuit increases by adding more loads in parallel


  false
• The rapid transfer of electrons from one object to another produces a

  electric discharge
• An object can be made negative by

  Gaining electrons
• Electrical resistance

  A materials ability to oppose the movement of electrons
• What best describes how length and temperature factor resistance of a wire

  As length and temperature increase the internal resistance increases
• Current electricity

  The continuous flow of charge in a circuit