Question

___________ is the percentage ratio of (effective operating time of machine) $\div$ (effective operating time + turning time) of machine.

• A. Performance efficiency
• B. Comparative index
• C. Field machine index
• D. Time efficiency

Hint:

Difference between Field Efficiency and Field Machine Index:
- Field Machine Index accounts for time lost only during turning (\(T_p + T_t\)).
- Field Efficiency accounts for all time losses in the field (turning, refilling, repairs, adjustments).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Field efficiency and related performance indices are measures used in agricultural engineering to evaluate the operating performance and time utilization of farm machinery during field operations.
Key Formula or Approach:
The Field Machine Index is mathematically expressed as:
\[ \text{Field Machine Index} = \frac{T_p}{T_p + T_t} \times 100 \] Where:
- \(T_p\) is the primary productive time (effective operating time)
- \(T_t\) is the time spent turning at the headlands of the field

Step 2: Detailed Explanation:
Let us analyze the definitions of the various terms:
- Field Machine Index (C):
This is specifically defined as the percentage ratio of the effective operating time of a machine to the sum of the effective operating time and the turning time.
It isolates the time lost solely due to turning at the ends of rows, making it a valuable index for evaluating field layout and row length.
- Time Efficiency (D):
This is the percentage ratio of the effective operating time to the total time spent in the field (which includes turning, adjustments, seed/fertilizer refilling, and clearing blockages).
- Performance efficiency (A):
This evaluates the quality of work done by the machine (such as grain loss in a harvester or weeding efficiency) compared to a standard.
Therefore, the defined percentage ratio is the Field Machine Index.

Step 3: Final Answer:
The percentage ratio of effective operating time to the sum of effective operating time and turning time is called the Field machine index.