Ammeter

Ammeter is an instrument that measures the flow of electrical current in amperes.

Symbol of Ammeter

The given below figure shows the symbol used to indicate an Ammeter.

Ammeter symbol

An Ammeter is always connected in series to the element through which the flow of current should be measured as shown in the below figure. It is because the current is common in a series circuit. An Ammeter should have very low impedance else if the ammeter has high impedance it will reduce the current in the circuit in which it connected. An ammeter should never be connected in parallel. As it has very low impedance, if it is connected in parallel it will allow high current and result in short circuit. Hence it must be always avoided.

Circuit for connecting an ammeter

Electric Current

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Electric Current

The flow of Electric charge particles is called as electric current. In electric circuits the charge is  carried by the movement of electrons through a conducting material called as conductor.

The loosely bounded electrons that appear in metals are called as conduction electrons. These conduction electrons move freely throughout the metal and they function as charge carriers. Thus in conductors, the current is due to