Question

Why is positive terminal of ammeter connected to positive terminal of battery ? When should we have alternate terminal in cases other than battery

Answer 1

Dear student, In ammeter pointer reads with its zero at one extreme end. So as polartiy gets changed then current flows in reverse direction and needle goes opposite which is harmful to ammeter and more over we cannot get any valuable reading marked on the device.this is regarding the ammeter used in DC Circuit While in A.C .there is no need of terminals( positive or negative terminal), you can connect in any manner in series. And ammeter used in A.C circuit measures RMS ( root mean square) value of current. Regards