Electrical current

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Electric current

  •         Controlled movement of electrons through a substance.
  •         Random motion of electrons will not constitute current unless there is a net transfer of charge with time.
  •           Rate of transfer of electric charge.
  •           Unit: ampere (A) or coulomb/second.
  •          Conventional direction of current is from positive potential to negative.
  •           Electrons will flow from negative potential to positive.
  •           Current flows when a potential difference exists across the terminals of a closed electrical circuit.

Note:
  •        Charge is something body attains when it loses or gains an electron.
  •        Unit of electric charge is Coulomb.
  •        Like charges repel each other and unlike charges attract each other.
  •       Proton posses a positive charge where as electron will have a negative charge.


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