英语翻译Scientists long reasoned that,since water has the unusual property of being less dense as a solid than as a liquid,its melting point can be lowered with an increase in pressure.While this is true,even the sharpest of skates raises the mel
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/16 09:56:44
英语翻译Scientists long reasoned that,since water has the unusual property of being less dense as a solid than as a liquid,its melting point can be lowered with an increase in pressure.While this is true,even the sharpest of skates raises the mel
英语翻译
Scientists long reasoned that,since water has the unusual property of being less dense as a solid than as a liquid,its melting point can be lowered with an increase in pressure.While this is true,even the sharpest of skates raises the melting point by only a few degrees.The pressure theory doesn’t hold water unless the ice is pretty warm already.Something else must be going on.
Some studies suggest that friction from a moving shoe,skate or tire causes the heat necessary to melt the ice beneath it.But what if the shoe isn’t moving at all?A second theory proposes that ice inherently has a fluid layer,caused by the motion of surface molecules that have nothing above to bind to and so move around in search of stability.The slippery culprit may be a combination of these two theories.
英语翻译Scientists long reasoned that,since water has the unusual property of being less dense as a solid than as a liquid,its melting point can be lowered with an increase in pressure.While this is true,even the sharpest of skates raises the mel
科学家长期的记录显示,由于水具有不同寻常的特征--液体状态下的水比固体状态下的密度低,它的熔点会随着压力的增加而降低.事实上这是真的,甚至是最锋利的溜冰鞋也会将冰的熔点上升几度.但当冰的温度较高的时候,这种观点就站不住脚了.会有一些其它的变化.
一些研究表明,由一双移动的鞋子,溜冰鞋或轮胎产生的磨擦都会到达使冰融化的温度.但是如果鞋子没有动呢?第二种理论证明冰本身就有流动层,这是由于冰的表面没有固定的分子移动以便寻找固定的位置造成的.
这些冰之所以滑的原因正体现在这两种理论的共同作用上.