From which category ‘Sigma comparator’ belongs?
A) Optical comparator
B) Mechanical comparator
C) Mechanical-optical comparator
D) Pneumatic comparator
Answer:
B) Mechanical comparator
Explanation:
A Sigma comparator is a mechanical comparator that compares two values. One or more of the following components are used in sigma comparators: a plunger; knife-edge; cross strip hinge; Y-shaped arm; drive drum; slit diaphragm; scale; and a pointer, among other things.