Question

How is an ammeter connected in a circuit?

• A. In series with the branch where you want to measure current, with the current flowing into the positive and out of the negative of the device.
• B. In parallel with the branch where you want to measure current, with the current flowing into the positive and out of the negative of the device.
• C. In series with the branch where you want to measure current, with the current flowing into the negative and out of the positive of the device.
• D. In parallel with the branch where you want to measure current, with the current flowing into the negative and out of the positive of the device.

Answer 1

The correct option is A In series with the branch where you want to measure current, with the current flowing into the positive and out of the negative of the device.

The ammeter has to be in the branch where current is to be measured. Or in other words, it has to be in series with the branch where current is to be measured. Next, the positive and negative terminals follow the convention that current has to flow into the positive and out of the negative terminal. You have to always be careful to connect the device in this way. You don’t want to risk damaging the device.
The galvanometer on the other hand, swings both ways. That is, its needle can rotate both ways and hence tell you the direction of current. It can be connected with current flowing into either terminal.