Crushing-law constants: the constants in Bond’s, Rittinger’s, and Kick’s laws (Kb, Kr, Kk) depend primarily on what factors?

Introduction / Context:
Energy–size reduction laws (Kick, Rittinger, Bond) use empirical constants to relate energy input to size change. These constants are not universal; they reflect both the material being crushed and the machine/process conditions.

Given Data / Assumptions:

• Kk (Kick), Kr (Rittinger), Kb (Bond) appear in their respective energy relations.
• We are deciding what they depend on.

Concept / Approach:
Material properties (hardness, fracture toughness, structure, moisture) strongly affect breakage work. Machine class (jaw, gyratory, roll) and operating conditions (speed, nip, liner profile) also influence the measured constant during testing.

Step-by-Step Solution:
Recognize that constants are calibrated from tests on specific materials and machines.Therefore, they depend on both feed characteristics and the crusher type/operating conditions.Select “both (a) & (b).”

Verification / Alternative check:
Work index data are tabulated by material, and test protocols specify equipment—evidence that constants are contextual.

Why Other Options Are Wrong:
Material only or machine only is incomplete.“Neither” contradicts empirical calibration practice.

Common Pitfalls:
Treating constants as universal numbers transferable across materials and crushers without recalibration.

Final Answer:
both (a) & (b)