1
$\begingroup$

I always thought it's because, if we consider a circuit ABCDE with only a battery and an ammeter, if we connect the negative terminal to the positive terminal the sum of the voltages across loops ABCDE would not be zero. Is that the actual reason, or is it because of something else?

$\endgroup$
1
  • $\begingroup$ Where is ammeter connected to a battery? You can connect terminals of ammeter to any two points you wish, but some choices may be dumb/dangerous. $\endgroup$ Dec 8, 2020 at 16:21

1 Answer 1

4
$\begingroup$

It is just a labelling convention which will give you a positive reading on the ammeter if a current enters the ammeter at the red terminal and a negative reading if the current leaves the ammeter from the red terminal. With moving coil meters a current entering the positive terminal will deflect the needle/spot of light to the right.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.