Question

Given below are two statements:

Statement (I): Drift is more serious problem with dusts compared to sprays.

Statement (II): Drift can be minimized by producing sprays having small volume mean diameter (VMD).

In light of the above statements, choose the most appropriate answer from the options given below.

• A. Both Statement (I) and Statement (II) are correct.
• B. Both Statement (I) and Statement (II) are incorrect.
• C. Statement (I) is correct but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

Think about whether fine or coarse droplets resist wind drift better.

Answer 1

The Correct Option is C

Step 1: Dust particles are fine, dry solids with almost no mass compared to their surface area. They float on the smallest breeze and travel far before settling, so drift is genuinely a bigger problem with dusts than with sprays. Statement (I) is correct.

Step 2: Volume mean diameter (VMD) tells us the average droplet size in a spray. A small VMD means very fine droplets, and fine droplets behave just like dust, they are light and drift easily on wind.

Step 3: So a spray with a small VMD would drift MORE, not less. The correct way to cut drift is to use a LARGER VMD, coarser droplets that fall straight down onto the target instead of floating away. Statement (II) has this backwards, so it is incorrect.

Step 4: Since (I) is correct and (II) is incorrect, option 3 is the answer.