Contact angle a contact angle of 0°. This is often the case for water on bare metallic or ceramic surfaces, although the presence of an oxide layer or contaminants on the solid surface can significantly increase the contact angle. Generally, if the water contact angle is smaller than 90°, the solid surface is considered hydrophilic and if the water contact angle is larger than 90°, the solid surface is considered hydrophobic. Many polymers exhibit hydrophobic surfaces. Highly hydrophobic surfaces made of low surface energy (e.g. fluorinated) materials may have water contact angles as high as ~120°. Some materials with highly rough surfaces
Less-is-better effect of top-quality candy than a box containing those 24 pieces plus 16 lower-quality pieces. If a manufacturer has developed two versions of a product and wishes to know which will be more popular with consumers and should therefore be put on the market, presenting them jointly to the public will enable consumers to evaluate differences between them, while presenting them separately will better predict the consumer's actual experience of the product when and if it is actually put on sale. Less-is-better effect The less-is-better effect is a type of preference reversal that occurs when the lesser or smaller alternative of