Subtopic: Rasp bar, spike tooth and axial flow cylinders
Question Statement:
Which of the following statements is/are TRUE regarding agricultural machinery engineering and field operation parameters?
Options:
(A) Effective field capacity is always less than theoretical field capacity due to turning, idle travel, and interruptions
(B) Field efficiency is the ratio of effective field capacity to theoretical field capacity expressed as a percentage
(C) Specific draft is defined as the draft force per unit cross-sectional area of tilled soil
(D) In combine harvesters, threshing cylinder peripheral speed is typically higher for wheat than for soybean to prevent seed cracking
Answer Key:
A, B, C, D
Step-by-Step Solution & Explanation
1. Turning time, seed filling, and unclogging reduce practical capacity below the ideal theoretical rate. (A is true)
2. $\eta_f = (\text{EFC} / \text{TFC}) \times 100$. (B is true)
3. $\text{Specific draft} = \text{Draft} / (w \times d)$ in $\text{N/cm}^2$. (C is true)
4. Soybean requires lower cylinder speeds ($12 - 18\text{ m/s}$) to prevent seed coat rupture, whereas wheat is threshed at $25 - 30\text{ m/s}$. (D is true)
All statements A, B, C, D are true.