When using an ammeter, what must you ensure about the connection?

When using an ammeter, it is essential to connect it in series with the circuit. This is because an ammeter is designed to measure current flow and, to do so accurately, it needs to become part of the current path. When connected in series, the ammeter allows the same amount of current to flow through it as flows through any other component in the circuit.

If an ammeter were connected in parallel, it would create a short circuit across the components, potentially damaging both the ammeter and the circuit itself. Additionally, connecting it to only resistors or disconnecting it would not allow for any current to be measured, thus defeating the purpose of the instrument.

By ensuring the ammeter is in series, you maintain the integrity of the circuit and obtain an accurate measurement of the current flowing through the system.