In a roll crusher, which statements about the two rolls are generally true?

Introduction / Context:
Roll crushers consist of two cylindrical rolls set close together, drawing particles into the gap for compression and shearing.

Concept / Approach:
Standard practice uses equal-diameter rolls, rotating towards each other at the nip to draw in material. Speed can be equal or deliberately differential to increase shear and improve nip efficiency for certain materials.

Final Answer:
All of the above