Why Ammeter is joined in series?

An ammeter is a device used to measure the flow of current in an electrical circuit. It measures the current passing through a specific point in the circuit. Ammeters are always connected in series with the circuit element or components whose current needs to be measured. This is done for the following reasons:

Accuracy:
When an ammeter is connected in series, it becomes an integral part of the circuit through which the current is flowing. By joining the ammeter in series, it allows the entire current to pass through it, ensuring accurate measurement of the current without disturbing the circuit.

Current Measurement:
The ammeter is designed to have a very low resistance, known as the internal resistance. When connected in series, the resistance of the ammeter is effectively in parallel with the circuit element whose current is being measured. This ensures that the ammeter does not significantly alter the total resistance in the circuit and thus does not affect the current being measured.

Protection:
Connecting the ammeter in series provides protection to the meter itself. As the ammeter is designed to measure the current passing through it, connecting it in series ensures that it only measures the current flowing through the circuit and not any other stray currents. This protects the ammeter from damage that could occur if it were connected in parallel.

Why Voltmeter is joined in parallel combination?

A voltmeter is an instrument used to measure the potential difference or voltage across a certain component or between two points in an electrical circuit. Voltmeters are connected in parallel with the circuit element or components whose voltage needs to be measured. This is done for the following reasons:

Voltage Measurement:
When a voltmeter is connected in parallel, it provides a parallel path for the current to flow. This allows the voltmeter to measure the potential difference across the desired circuit element without significantly altering the current or voltage in the circuit. The voltmeter measures the voltage drop across its terminals, which is equivalent to the potential difference across the desired component.

High Resistance:
Voltmeters are designed to have a very high resistance, known as the internal resistance. When connected in parallel, the high resistance of the voltmeter ensures that it draws a minimal amount of current from the circuit, preventing any significant alteration in the voltage being measured.

Protection:
Connecting the voltmeter in parallel provides protection to the meter itself. As the voltmeter is designed to measure the voltage across a specific component or points in the circuit, connecting it in parallel ensures that it only measures the voltage drop across the desired element and not any other stray voltages. This protects the voltmeter from damage that could occur if it were connected in series.

In summary, ammeters are joined in series with the circuit elements to accurately measure the current without altering the circuit, while voltmeters are connected in parallel to measure the voltage drop across specific components without significantly affecting the circuit.