Q41: Given below are two statements: Statement (I) : Drift is... - Farm Machinery, Farm Power & Renewable Energy Engineering - ICAR AIEEA PG Agricultural Engineering & Technology 09 July 2023 (Shift 1) Paper | Agrigyan

Detailed Analysis of Spray and Dust Drift:

• Statement (I) is Correct: Pesticide dusts consist of microscopic dry powder particles ($\lt 20\text{--}30\ \mu\text{m}$) that have extremely low mass and terminal settling velocity, making them highly prone to long-distance airborne drift even under mild air currents. Consequently, chemical recovery in target fields from dusting rarely exceeds 10–20% compared to 70–80% for liquid sprays.
• Statement (II) is Incorrect: Droplets with small Volume Mean Diameter (VMD $\lt 100\text{--}150\ \mu\text{m}$) evaporate rapidly and remain suspended in air, causing severe drift. To minimize spray drift, operators must INCREASE the VMD (producing larger, coarser droplets $\gt 250\text{--}300\ \mu\text{m}$) and use air-induction nozzles.