Difficulty: Easy
Correct Answer: Rittinger’s law
Explanation:
Introduction / Context:
Energy–size reduction relationships help estimate power requirements and select suitable grinders. Three classic laws—Rittinger, Kick, and Bond—apply in different size ranges and fragmentation regimes.
Given Data / Assumptions:
Concept / Approach:
Rittinger’s law: E ∝ ΔA (increase in surface area). Kick’s law: E ∝ ln(d1/d2). Bond’s law: E ∝ (1/√d2 − 1/√d1). Thus, only Rittinger directly ties energy to new surface created, matching systems where fracturing creates many fines.
Step-by-Step Solution:
Identify law with energy–surface proportionality.Match to Rittinger’s statement.Select Rittinger’s law.
Verification / Alternative check:
Fine grinding design commonly references Rittinger for micronization contexts, validating the selection.
Why Other Options Are Wrong:
Taggart’s rule: screening/misc. correlations, not energy law.Fick’s law: diffusion, unrelated to grinding energy.Kick/Bond: different functional forms, not directly to surface area.
Common Pitfalls:
Confusing Bond’s widely used work index with Rittinger’s fine-grinding emphasis.
Final Answer:
Rittinger’s law
Discussion & Comments