Question

What is the tolerance of the straightness of a line?

(a) Maximum deviation from the straight line joining two extremities

(b) Maximum deviation from the middle point of straight line joining two extremities

(c) Minimum deviation from the straight line joining two extremities

(d) Minimum deviation from the middle point of straight line joining two extremities

This question was addressed to me at a job interview.

The doubt is from Straightness in chapter Straightness, Flatness, Squareness, Parallelism, Circularity and Rotation of Engineering Metrology

Answer 1

The correct option is (a) Maximum deviation from the straight line joining two extremities

To explain: The tolerance on the straightness of a line can be  defined as the maximum deviation in

relation to the reference straight line joining the two extremities of the line to be checked. Tolerance is used to confirm that a part is uniform over a surface. More straightness is present with less tolerance.