Assertion: vulture's wing | /r/HasProperty | concave
Facets:
value: because of this shape
type: CAUSE
value: on convex
type: LOCATION
Source sentences:
text: Vulture’s wings are concave on their underside and convex on the upper surface, because of this shape the air that travels over the wing has a greater distance to travel resulting in it speeding up, this causes the pressure to drop (this is because the same amount of air is exerting its pressure over a larger area above the wing than below it.