The ratio of the area of openings in one screen (Taylor series) to that of the openings in the next smaller screen is given by the square root of 2, denoted as √2. This ratio is based on the Taylor series for mesh sizes in screens commonly used in mechanical operations.
Therefore, in this context, the correct option is Option C: √2 (Square Root of 2).
Crushing of mineral particles is accomplished in a 'cage mill', when one or more alloy steel bars are revolved in opposite directions. It is a type of __________ mill.