Word: lifts
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Dates: during 1940-1949
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...their own candidates, although their campaigning was restricted. (They need travel permits, and may not hold public meetings in areas occupied by the Israeli army.) Last week in Arab Nazareth, Moslem women complained that their religion forbade them to be photographed for identity cards or to lift their purdahs for identification at the polls in the presence of men. After some head-scratching, the government's election committee decided that Arab women could vote without having their pictures taken. Furthermore, there would be a special force of female poll watchers before whom the Arab women voters could lift their...
...reaction between its stationary wings and the air that strikes them as the plane moves horizontally. A bird is supported in the same way. The broad inner portions of its wings, which move less than the tips, are kept at any angle of attack that gives them maximum lift...
Slots & Flaps. The lift in an airplane's wings can be increased by increasing the angle of attack (i.e., the angle at which it meets the air stream). If the angle becomes too great, the air stream does not flow smoothly over the wing; it breaks into turbulent eddies. The wing loses most of its lift, and the stall that results can throw the airplane, into a disastrous spin. The danger of stalling can be lessened by slots behind the leading edge of the wing. The slots feed thin layers of air to the wing's upper side...
...wings of many birds are also slotted so that the angle of attack (and the lift) may be increased without risking a stall. They have a movable feather called an "alula," which usually rests against the leading edge. When the bird needs extra lift from its wings (i.e., for a quick, high-angle climb), it increases its wings' angle of attack. Then it opens a slot by moving the alula. A thin stream of air rushes over the wing, preventing a stall...
...flies too slowly. Birds, like planes, are equipped with "flaps": movable sections which can be protruded from the trailing edges of the wings. When slowing down for a landing, birds often spread their tails at a proper angle of attack. The tail acts exactly like airplane flaps, providing extra lift and keeping the bird from stalling...