Question Bank • QB_PARAMETRIC_FM_MB_004MCQ • 1 Mark
Section 2: Farm Machinery
Primary Tillage: Mouldboard Ploughs & Forces
Subtopic: Specific draft calculation
Question Statement:
A single-bottom mouldboard plough has a width of cut of $29\text{ cm}$ and operates at a depth of $16\text{ cm}$. If the specific soil draft is $0.8\text{ N/cm}^2$, the total draft required by the plough bottom is: (Variation QB_PARAMETRIC_FM_MB_004)
Options:
(A) $371.2\text{ N}$
(B) $445.4\text{ N}$
(C) $297.0\text{ N}$
(D) $556.8\text{ N}$
Answer Key:
A
Step-by-Step Solution & Explanation
The total draft $D$ is the product of cross-sectional area of the furrow slice and the unit draft (specific draft):
$\text{Cross-sectional Area } A = w \times d = 29\text{ cm} \times 16\text{ cm} = 464\text{ cm}^2$
$\text{Total Draft } D = A \times \text{Specific Draft} = 464\text{ cm}^2 \times 0.8\text{ N/cm}^2 = 371.2\text{ N}$
Hence, the correct draft is $371.2\text{ N}$.