To measure the current, there is a choice of two ammeters X and Y. The scale on the face of each meter is shown in the following figures.
Which meter would you choose, given that the temperature of the coil is always between 0°C and 100°C?
We would choose meter Y because the range of current to be measured is very small, i.e. 0 to 0.4 mA.
The meter Ywill show a largest possible deflection for a current within this range reducing the error in the measurement of the current.