Question

What is ten point height of irregularities?

(a) Average difference between 10 highest peaks

(b) Average difference between 10 deepest valleys

(c) Average difference between 5 highest peaks and 5 deepest valleys

(d) Average difference between 10 highest peaks and 10 deepest valleys

The question was asked in exam.

The origin of the question is Terminology as per Indian Standards topic in division Measurement of Surface Finish of Engineering Metrology

Answer 1

Correct choice is (c) Average difference between 5 highest peaks and 5 deepest valleys

Explanation: Ten point height of irregularities is represented by Rz and defined as the average difference between the 5 highest peaks and the 5 deepest valleys within the sampling length measured from a line, not crossing the profile and parallel to the mean line.