Question

What is the formula of distance between centre of discs in the method of measurement of the angle of V-grooves using discs?

(a) (h2+h1)-((d2-d1)/2)

(b) (h2-h1)-((d2-d1)/2)

(c) (h2-h1)+((d2-d1)/2)

(d) (h2-h1)-((d2+d1)/2)

I had been asked this question in a job interview.

The above asked question is from Measure the Angle of a V-Groove in section Miscellaneous Measurements (EM) of Engineering Metrology

Answer 1

The correct choice is (b) (h2-h1)-((d2-d1)/2)

To elaborate: If O1 and O2 are the centres of the two balls used in this method and O1B is drawn parallel to one of the inclined surfaces & O2B is perpendicular to O1B. Then, O2O1B equals half the angle of V-groove and the distance between centres i.e. O1O2 is given by (h2-h1)-((d2-d1)/2).