Bevel gear ordinary gear is the shape of a cylinder. The pitch angle of a gear is the angle between the face of the pitch surface and the axis. The most familiar kinds of bevel gears have pitch angles of less than 90 degrees and therefore are cone-shaped. This type of bevel gear is called external because the gear teeth point outward. The pitch surfaces of meshed external bevel gears are coaxial with the gear shafts; the apexes of the two surfaces are at the point of intersection of the shaft axes. Bevel gears that have pitch angles of greater than ninety
Less-is-better effect Less-is-better effect The less-is-better effect is a type of preference reversal that occurs when the lesser or smaller alternative of a proposition is preferred when evaluated separately, but not evaluated together. The term was first proposed by Christopher Hsee. In a 1998 study, Hsee, a professor at the Graduate School of Business of The University of Chicago, discovered a less-is-better effect in three contexts: "(1) a person giving a $45 scarf (from scarves ranging from $5-$50) as a gift was perceived to be more generous than one giving a $55 coat (from coats ranging from $50-$500); (2) an overfilled ice