It has been proven that electrons (negative charges) move through a conductor in response to an electric field.

Electron current is defined as the directed flow of electrons.

The direction of electron movement is from a region ofnegative potential to a region of positive potential. Therefore electric current can be said to flow from negative to positive.

The direction of current flow in a material is determined by the polarity of the applied voltage.

NOTE: In some electrical/electronic communities, the direction of current flow is recognized as being from positive to negative.

The magnitude of current is measured in AMPERES. A current of one ampere is said to flow when one coulomb of charge passes a point in one second. Remember, one coulomb is equal to the charge of 6.28 x 10 to the 18 electrons.

Frequently, the ampere is much too large a unit for measuring current. Therefore, the MILLIAMPERE (mA), one-thousandth of an ampere, or the MICROAMPERE (one-millionth of an ampere),is used. The device used to measure current is called an AMMETER.

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