Vernier Caliper
A precision measuring instrument utilizing a main scale and a sliding Vernier scale to measure linear dimensions with fine precision.
Governing formula
Reading = Main Scale + (Vernier Coincidence × Least Count)
SI unit
mm
In depth
The Vernier scale aligns N-1 main scale divisions with N Vernier divisions, allowing fractional measurements far smaller than the main scale division without digital electronics.
Examples in the real world
Measuring the outer diameter of a steel cylinder or the depth of a narrow cylindrical hole.