The correct option is In series.
Explanation
An ammeter is an instrument used to measure the magnitude of electric current flowing through a circuit. To accurately measure the rate of flow of charge (current), the instrument must be placed directly in the path of the flow.Detailed Analysis:
- Series Connection: In a series combination, the electric current remains the same through all components connected in the line. Therefore, an ammeter is connected in series with the circuit element so that the entire current flowing through the element also passes through the ammeter.
- Resistance Characteristics: To ensure the insertion of the ammeter does not alter the circuit conditions, it is designed to have very low resistance. If it had high resistance, it would significantly reduce the current it is trying to measure.
- Why not Parallel? If an ammeter were connected in parallel, its low resistance would create a short-circuit path. Most of the current would bypass the component and flow through the ammeter, potentially damaging the instrument due to excessive current and failing to measure the current through the intended component.
Key Takeaway:
An ammeter is always connected in series to measure current and possesses low resistance. Conversely, a voltmeter is connected in parallel to measure potential difference and possesses high resistance.