Question

What is an ammeter? How is it connected in a circuit? Draw a diagram to illustrate your answer.

Answer 1

Hint: In order to measure current in a circuit we use an ammeter. Current is the rate of flow of charge. Current is measured in the unit ampere.

Complete step by step solution:
An ammeter is an instrument which is used to measure current flowing in a circuit. We know that current is the rate of flow of charge. The SI unit of measuring current is ampere. The ammeter has a scale which represents current in ampere. The instrument got its name ammeter from ampere meter because it measures current in ampere.

For measuring large current we can use ammeters. In cases where the current flowing in the circuit is small, that is in the milliampere range or microampere range we should use ammeter in that range. Ammeter for measuring milli ampere current is named as milli ammeter and the ammeter used for measuring micro ampere current is named as microammeter.

An ammeter should be connected in series with the circuit for measuring current. In a circuit diagram ammeter is represented by a circle with the letter A. 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 connect the ammeter in series with the resistor as shown below. Then the reading in the ammeter will give us the current flowing through the circuit.

Note: An ammeter is a device used to measure current. In order to measure the current an ammeter should always be connected in series. Voltmeter is a device used to measure the voltage and voltmeter is always connected in parallel.