Question

What is the limitation of microscopic inspection to check surface finish?

(a) An average value is needed

(b) Small portion of surface can be detected at a time

(c) A master finish surface is also needed

(d) It is necessary to inspect whole surface together

I had been asked this question in an international level competition.

I want to ask this question from Methods of Measuring Surface Finish in portion Measurement of Surface Finish of Engineering Metrology

Answer 1

The correct answer is (b) Small portion of surface can be detected at a time

Easy explanation: Microscopic inspection method have some limitation that at a time only a small portion of the surface can be inspected. So for inspection, several readings are required in this method to get an average value.