Question

Consider the following statements related to harvesting knife
A. Fine knife has small bevel angle
B. Blunt knife has large edge radius
C. Sharp knife has small edge radius
D. Dull knife has small bevel angle
Choose the correct answer from the options given below:

• A. A and C only
• B. B and D only
• C. B and C only
• D. A, B, C and D

Hint:

- Bevel Angle determines the wedge thickness and is set during manufacturing.
- Edge Radius determines the sharpness of the tip and changes as the blade wears down over time.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Cutting and harvesting tools rely on wedge-shaped blades to slice through plant stalks.
The cutting action is determined by the blade's geometry, which includes the bevel angle and the edge radius.
Detailed Explanation:
Let us evaluate each statement based on cutting tool principles:
- Statement A:
The bevel angle is the angle formed by the sloped sides of the blade's wedge.
A fine, delicate knife is designed with a small bevel angle (typically 15\(^\circ\) to 20\(^\circ\)), which reduces cutting resistance.
Thus, Statement A is correct.
- Statement B:
The edge radius is the radius of curvature at the very tip of the cutting edge.
A blunt or worn knife has a rounded tip, which corresponds to a large edge radius.
Thus, Statement B is correct.
- Statement C:
A sharp knife has a highly defined, pointed tip, which corresponds to an extremely small edge radius (often measured in micrometers).
Thus, Statement C is correct.
- Statement D:
In cutting mechanics, a dull knife retains its original designed bevel angle (which can be small).
However, it has lost its sharpness because the tip has worn down, increasing the edge radius.
Therefore, in terms of blade classification and design, all four statements accurately describe these geometry and wear relationships.

Step 2: Final Answer:
All four statements (A, B, C, and D) are correct.