Physics - Electricity

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Created by
Tommy

Cards (10)

  • Learn circuit symbol.
  • Current is the rate of flow of charge and has the symbol (I). Current is measured in Amperes and is measured using an ammeter.
    Q=IT
  • The coulomb is the unit of charge. One coulomb is defined as the amount of charge that passes in 1 second when the current is 1 ampere.
  • What is the purpose of the power source in a circuit?
    To provide electrical energy. Therefore, to transfer energy to the unit of charge.
  • The potential difference between two points is the work done in moving a unit of charge between the two points
  • Potential difference:
    V=W/Q
    Potential difference is measured in volts and it is the energy given to a unit of charge.
  • Resistance is a measure of how hard it is for current to flow. Measured in ohms.
    The following equation defines resistance
    R=V/I
  • Conductors that obey ohms law are called ohmic conductors.
  • Ohms law states that I is directly proportional to V for all values of V. Resistance is 1/gradient and is therefore a fixed value for a straight line graph (so for a conductor that obeys ohms law).
  • Factors like light level or temperature will have a significant effect on resistance. Therefore, Ohms law is only true for ohmic conductors under physical conditions.