A single-bottom mouldboard plough has a width of cut of $26\text{ cm}$ and operates at a depth of $13\text{ cm}$. If the specific soil draft is $0.5\text{ N/cm}^2$, the total draft required by the plough bottom is:
Options:
(A) $169.0\text{ N}$
(B) $202.8\text{ N}$
(C) $135.2\text{ N}$
(D) $253.5\text{ N}$
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):
$\text{Cross-sectional Area } A = w \times d = 26\text{ cm} \times 13\text{ cm} = 338\text{ cm}^2$
$\text{Total Draft } D = A \times \text{Specific Draft} = 338\text{ cm}^2 \times 0.5\text{ N/cm}^2 = 169.0\text{ N}$
Hence, the correct draft is $169.0\text{ N}$.