Question

What is the resolution of a 3 digit display on 1 V range?

(a) 1 V

(b) 0.1 V

(c) 0.01 V

(d) 0.001 V

The question was asked in unit test.

This interesting question is from Resolution and Sensitivity topic in section Electronic Instruments of Electrical Measurements

Answer 1

Right option is (d) 0.001 V

For explanation I would say: The resolution of a DVM is,

R = ^1⁄10^n

Here, n is 3. Substituting n=3 in the equation for resolution we get,

R = ^1⁄10^3 = 10^-3 = 0.001

For 1 V range, the resolution is,

R1V = 1×0.001 = 0.001 V.