According to Rittinger’s law for crushing and grinding, the energy required is directly proportional to which quantity?

Introduction / Context:
Comminution energy models help estimate power requirements across size ranges. Rittinger’s law applies best to fine grinding where surface area increases significantly.

Given Data / Assumptions:

• Focus on the proportionality statement.
• No numeric data required.

Concept / Approach:
Rittinger’s postulate: E ∝ ΔA (increase in surface area). It contrasts with Kick’s law (E ∝ ln size ratio) and Bond’s law (E ∝ 1/√d relationships). Therefore, for fine size targets, Rittinger provides the most accurate estimate.

Step-by-Step Solution:
Identify the law linking energy to surface area.Select “new surface created.”

Verification / Alternative check:
Textbook derivations and experimental evidence in fine milling confirm the proportionality to ΔA.

Why Other Options Are Wrong:
Size ratio or volume change are not Rittinger’s basis.

Common Pitfalls:
Confusing Bond’s widely used industrial correlations with Rittinger’s fine-grind regime.

Final Answer:
The new surface created