Question

An ammeter has 20 divisions between 0 mark and 2 A mark on its scale. The least count of this ammeter is:
(A) 0.01 A
(2) 0.02 A
(3) 0.1 A
(4) 0.2 A

Answer 1

The least count of any device is given by the value measured by one single division on the scale of the device.

Total number of divisions on the scale of the given ammeter = 20

least count = $\frac{2\text{A}}{20}\text{= 0.1 A}$

Hence, the correct answer is option 3.