S2 Ch13 (ES)

• What is the SI unit for resistance?

  Ohm (Ω)
• What is the SI unit for current?

  Ampere (A)
• What is the SI unit for potential difference?

  Volts (V)
• What is the formula for resistance?

  Resistance = potential difference / current
• Electron flow is from which end to which end?

  Negative to positive
• Positive side of ammeter connects to the positive end of cell
• Ammeter is connected in?

  Series
• Voltmeter is connected in?

  Parallel
• Define electric current (I)

  An electric current, I, is the rate of flow of electric charges
• Define potential difference (V)

  The potential difference across a component is the amount of work done to drive a unit charge through the component
• Define electrical resistance

  Electrical resistance of an electrical component is a measure of how much the component opposes the flow of electric current
• Which wire are switches connected to?

  Live wires (S)
• Which wire are circuit breakers connected to?

  Live wire (CB)
• Which wire are fuses connected to?

  Live wire (F)
• Which wire is connected to high voltage and delivers the current to appliance?

  Live wire
• Which wire completes the circuit and provides the returning path?

  Neutral wire
• Which wire is the low resistance wire connected to metal casing of appliances and prevents electric shocks?

  Earth wire
• Which circuit arrangement has same current everywhere?

  Series
• Is current the same in every part of a parallel circuit?

  No
• What is the SI unit for power?

  Watt (W)
• What is the SI unit for electrical energy?

  kWh
• What is the formula for electrical energy?

  Electrical energy = Power x Time