A low contact angle indicates what about wettability?

A low contact angle indicates what about wettability?

• A. Higher wettability
• B. Lower wettability
• C. No wettability
• D. Unknown

Answer: (A)

Wettability is about how well a liquid spreads on a surface. A low contact angle means the liquid makes a small angle with the surface, so it spreads out more and covers more of the surface. That spreading is a sign of high wettability. If the angle were large, the liquid would bead up, covering less area, which means lower wettability. The other options don’t fit because no wettability would require little to no spreading (a very high angle), and unknown isn’t indicated by a measured angle. In soft contact lenses, better wettability helps the tear film spread more evenly over the lens, improving comfort.

Wettability is about how well a liquid spreads on a surface. A low contact angle means the liquid makes a small angle with the surface, so it spreads out more and covers more of the surface. That spreading is a sign of high wettability. If the angle were large, the liquid would bead up, covering less area, which means lower wettability. The other options don’t fit because no wettability would require little to no spreading (a very high angle), and unknown isn’t indicated by a measured angle. In soft contact lenses, better wettability helps the tear film spread more evenly over the lens, improving comfort.