時差N小時:箱子底部的玉米薄片為什么不會被壓碎(下)

　　The friction between the flakes is the same forcethat causes sand to form a pile rather than spreadout like a puddle. In fact, this same principleapplies to all granular materials. If you cut thecorner out of a bag of flour only a small amount willcome out. If the bag contained water, which has lowfriction, all of it would run out. Incidentally, thereare broken flakes and cereal “dust” in boxes, butthis is the result of shaking during shipping andhandling, not simply the weight of the upper flakeson the lower ones. The effect of friction is veryimportant in the cereal manufacturing process, which involves huge vats of flakes. Even inthose vats the friction-induced weight distribution keeps the bottom flakes from being turnedto dust, and allows whole flakes to tumble into our breakfast bowls.

　　薄片之間的摩擦力和使沙形成堆，而不是分散開形成水坑形狀是一樣的力量。事實(shí)上，這一原則同樣適用于所有顆粒狀物料。如果你砍了一袋面粉的一角球，只有少量面粉會流出來。如果用包裝水，那樣摩擦力很小，水都會流盡。順便說一下，盒子里會有破損的薄片和谷物 “粉末”，但是這是在運(yùn)輸和裝卸過程中搖晃的結(jié)果，而不是單純的上部薄片壓擠下面薄片的結(jié)果。摩擦的作用在薄皮生產(chǎn)過程中是非常重要的，它涉及到裝薄皮的巨桶。即使在這些大桶中的摩擦引起的重量分布會避免使底部的薄皮變成粉末，使薄皮整片倒進(jìn)我們的早餐碗中而不碎。

　　granular adj.由小粒而成的; 粒狀的 incidentally adv.順便說及地，順便提一句 vat n. 大桶 tumble v.翻倒