Agricultural Engineering and Farm Machinery
What this domain tests
Agricultural Engineering and Farm Machinery tests farm power, tillage, implements, seed drills, irrigation, threshing, machinery selection and farm safety. Numeric questions on field capacity, seed rate and water requirement are common.
Core rules and concepts
- Farm power sources include human, animal, tractor, diesel engine, electric motor and renewable sources. Power is measured in kW or hp; 1 hp = 0.746 kW.
- Primary tillage breaks and inverts soil; secondary tillage prepares a fine seedbed.
- A seed drill meters seed and fertilizer; calibration checks the actual seed delivery per metre or per hectare.
- Theoretical field capacity (ha/h) = width (m) × speed (km/h) ÷ 10. Effective field capacity is lower because of turns, loading, repairs and rest.
- Irrigation efficiency compares water stored in the root zone with water delivered; drip and sprinkler systems usually raise application efficiency.
- Safety guards, PTO shields and proper hitching prevent serious accidents.
Worked example
A 2 m wide implement is operated at 5 km/h. Theoretical field capacity = 2 × 5 ÷ 10 = 1.0 ha/h. If field efficiency is 80%, effective capacity = 1.0 × 0.80 = 0.8 ha/h. Time needed for 4 ha = 4 ÷ 0.8 = 5 hours. The reasoning is to calculate theoretical capacity first, then apply the efficiency factor; do not apply efficiency to the time.
Traps that cost marks
Do not mix metres with centimetres in the width. Do not use engine hp and PTO hp interchangeably. Do not report effective capacity as theoretical capacity. Do not ignore overlap and turning time. Do not calculate irrigation volume without converting depth (cm) to metres.