Current and Circuit Components

• How is current defined?

  As the rate of flow of charge around a circuit.
• Units of charge

  Coulombs, C
• In a series circuit the total voltage is shared between each component.

  In a parallel circuit the voltage across each component is the same.
• If two resistors are connected in parallel, what can be said about their combined total resistance?

  Their total resistance is less than the smallest of the two individual resistances.
• If two resistors are connected in series, what can be said about their total resistance?

  The total resistance in a series circuit is equal to the sum of the individual resistances.
• Where must a voltmeter be placed in a circuit?

  In parallel with the component being measured.
• Potential difference (V) =

  Energy transferred (J) / Charge (C)

  V = E / Q
• A volt can also be described as a…

  Joule per coulomb
• What is electric current?

  The rate of flow of charge.
• Charge =

  Current x time (s)
• What happens when current reaches a junction in a circuit?

  Current is conserved, the total current remains the same and is split between the two branches.