What motion should you use to wipe the sample area?

What motion should you use to wipe the sample area?

• A. Circular motions
• B. Linear back-and-forth
• C. S-like motions
• D. Wiping in circles

Answer: (C)

The motion should be S-shaped (serpentine). This pattern ensures the wipe covers the entire surface with overlapping strokes, so residues across the area are collected evenly and no spots are left unsampled. Circular motions tend to center on one area and can miss edges; linear back-and-forth can leave gaps at the ends; wiping in circles is basically another circular approach that doesn’t guarantee full coverage. The serpentine path provides continuous, thorough contact across the whole sample area.

The motion should be S-shaped (serpentine). This pattern ensures the wipe covers the entire surface with overlapping strokes, so residues across the area are collected evenly and no spots are left unsampled. Circular motions tend to center on one area and can miss edges; linear back-and-forth can leave gaps at the ends; wiping in circles is basically another circular approach that doesn’t guarantee full coverage. The serpentine path provides continuous, thorough contact across the whole sample area.