猫：我能喝到牛奶 又不弄湿下巴
Cats can drink milk without getting their chins wet According to the Daily Telegraph on November 12, a team of engineers, physicists and mathematicians conducted a three and a half year study to find out exactly how cats manage to move the milk from saucer to mouth, while keeping their chins dry in the process.And far from simply slurping at the bowl, researchers at MIT, Virginia Tech and Princeton University say the technique exhibits "a perfect balance between two physical forces". The tip of the cat's tongue scarcely brushes the liquid's surface before it is rapidly drawn back. This forms a column of milk between the tongue and the surface, which the cat captures by closing its mouth.This column is created by a balance between gravity pulling the liquid back to the bowl, and inertia - the tendency of a substance to move in a given direction until another force intervenes. Cats instinctively know how to strike this balance in order to time the lapping and to capture the liquid in their mouths, according to journal Science.Domestic cats average about four laps per second, with each lap bringing in about 0.1 milliliters of liquid, while big cats naturally lap more slowly to maintain the balance of gravity and inertia.Mathematician Jeffrey Aristoff said: "Our research — the experimental measurements and theoretical predictions — suggests that the cat chooses the speed in order to maximize the amount of liquid ingested per lap. This suggests that cats are smarter than many people think, at least when it comes to hydrodynamics."据英国《每日电讯报》11月12日报道，一个由工程师、物理学家和科学家组成的研究小组进行为期三年半的研究，发现猫是如何将碟子中的牛奶饮到嘴里，同时在这一过程中又能保持不弄湿自己的下巴。麻省理工学院、弗吉尼亚理工大学和普林斯顿大学研究人员表示，猫喝奶不仅仅是吮吸碗中牛奶，它们喝奶动作简直就是在进行"两种物理作用力的完美平衡"表演。猫的舌尖刚刚刷到牛奶的表面就迅速收回，这样猫的舌头和牛奶表面就形成一个"牛奶圆柱"，猫闭上嘴巴就可以喝到牛奶。重力将牛奶重新吸回碗里，而惯性将牛奶继续推向原来运动的方向，直到在重力的干预下回落，它们之间的平衡形成了"牛奶圆柱"。《科学》杂志说，猫本能地知道如何保持这两种力的平衡，以测算吮吸一次的时间，确保喝到牛奶。家猫每秒钟吮吸四次奶，每次大约能喝到0.1毫升的牛奶，而体型大的猫会自然放慢吮吸速度，以保持重力和惯性之间的平衡。数学家Jeffrey Aristoff表示："我们根据试验测算和理论预测进行的研究表明，猫会选择吮吸牛奶的速度，保证每次都能喝到最多的奶。这充分说明它们比人们想象中更聪明，至少在流体力学方面"。
呆呆虫 最后编辑于 2010-11-15 17:21:51
