What is a DC ammeter?

Hint: First we need to understand the function of a DC ammeter. In order to measure direct current in a circuit we use a DC ammeter. Current is basically defined as the rate of flow of charge and in case the current is flowing in one direction, then it is known as DC current. Current is measured in terms of the unit ampere.


Complete step by step solution:
A DC ammeter is an instrument which is used to measure the amount of DC current flowing in a circuit. The DC ammeter has a scale which represents current in ampere. The instrument got its name ammeter from ampere meter because it measures the amount of current in ampere.
For measuring large amounts of DC current, we can use DC ammeters. In cases where the current flowing in the circuit is very small, that is in the range of milliampere or microampere, then we should use an ammeter in that range.
A DC ammeter should always be connected in series with the circuit for measuring DC current. In terms of a circuit diagram, the ammeter is represented by a circle with the letter A. In this case, consider the following circuit with a resistor R and a voltage source.
If we want to measure the current flowing through the resistor then we should always connect the DC ammeter in a series combination with the resistor as shown in the figure below. Then the reading in the DC ammeter will give us the value of DC current flowing through the circuit.

Note:
A DC ammeter is a device used to measure current. In order to measure the DC current, the DC ammeter should always be connected in a series combination. There is another device known as Voltmeter which is used to measure the voltage and the voltmeter is always connected in parallel.