In order for a voltmeter to measure a device's voltage, it must be connected in parallel to that device . This is necessary because objects in parallel experience the same potential difference. n ammeter measures the electric current in a circuit. ... This is necessary because objects in series experience the same current.

**Why a voltmeter connects in parallel and an ammeter in series?**

A voltmeter is a measuring instrument used to measure the potential difference (voltage) across a component or circuit, while an ammeter is used to measure the current flowing through a component or circuit. The reason why a voltmeter connects in parallel and an ammeter connects in series is based on the principles of circuitry and the characteristics of these instruments.

1. **Voltmeter in parallel:**
- A voltmeter connects in parallel with the component or circuit being measured because its purpose is to measure the voltage across that specific component.
- When connected in parallel, the voltmeter provides a high resistance path for the current. This ensures that the current passing through the voltmeter is negligible, minimizing its impact on the circuit being measured.
- By measuring the voltage in parallel, the voltmeter ensures that it measures the potential difference across the component accurately, as it does not interfere with or alter the current flowing through the circuit.

2. **Ammeter in series:**
- An ammeter connects in series with the component or circuit being measured because its purpose is to measure the current flowing through that specific component.
- When connected in series, the ammeter becomes part of the current path. It has a very low resistance to allow the current to flow through it and provide an accurate measurement.
- By connecting in series, the ammeter measures the current passing through the component directly, without any parallel paths that could affect the current reading.

**Which is better: Series or parallel connection?**

The choice between series and parallel connection depends on the specific application and the desired measurement.

1. **Series connection advantages:**
- Series connection allows the ammeter to measure the current flowing through a specific component accurately.
- It provides a direct current path, minimizing any potential interference from parallel branches in the circuit.
- Series connection is useful when measuring the current drawn by a single component or evaluating the overall current flow in a series circuit.

2. **Parallel connection advantages:**
- Parallel connection allows the voltmeter to measure the voltage across a specific component accurately.
- It provides a high resistance path, ensuring minimal impact on the circuit being measured.
- Parallel connection is useful when measuring the potential difference across a single component or evaluating the voltage drop across different branches in a parallel circuit.

In conclusion, the choice between series and parallel connection depends on the type of measurement required. A voltmeter connects in parallel to accurately measure voltage, while an ammeter connects in series to accurately measure current. Both connections have their advantages and are used in different scenarios to obtain accurate measurements.