Subtopic: Functional requirements, principles of working, construction and operation of manual, animal, tractor and renewable energy operated equipment for tillage, sowing, planting, fertilizer application, inter-cultivation, spraying, mowing, chaff cutting, harvesting and threshing
Question Statement:
A precision maize planter moves forward at a speed of $v_f = 5.4\text{ km/h}$. The vertical cell plate seed metering disc has $n_c = 16$ cells uniformly spaced along its periphery. The transmission drive from the ground wheel rotates the disc at $N = 45\text{ rpm}$. Assuming zero wheel slip and $100\%$ cell fill, the theoretical spacing between consecutive seeds in the row in $\text{cm}$ is ________ (round off to 1 decimal place).
Answer Key:
12.5
Step-by-Step Solution & Explanation
1. Forward speed in $\text{cm/s}$:
$v_f = 5.4 \times \frac{5}{18} = 1.50\text{ m/s} = 150\text{ cm/s}$
2. Number of seeds dropped per minute:
$\text{Rate} = N \times n_c = 45 \times 16 = 720\text{ seeds/min}$
$\text{Seeds per second} = \frac{720}{60} = 12\text{ seeds/s}$
3. Seed spacing in row ($s$):
$s = \frac{v_f}{\text{Seeds per second}} = \frac{150\text{ cm/s}}{12\text{ s}^{-1}} = 12.5\text{ cm}$