The Formation of Ice托福听力原文翻译及问题答案

2023-04-14 15:29:11 来源：中国教育在线

新托福听力难度大，题型多，而且听力和写作、口语等部分也相关联，可以说，是牵一发而动全身的地位。所以要想取得高分，需要以残酷的、毫无疑问的、不存在任何侥幸的听力实力为基础。那么关于“The Formation of Ice托福听力原文翻译及问题答案”的内容，下面由小编来给大家分享。

一、The Formation of Ice托福听力原文：

W:I’m glad to see everyone made it to school safely this morning.I wish I could say the same for myself,but I had a rather close call when I was getting on the expressway.I was on the on-ramp,and my car suddenly skidded and turned completely around,so I ended up with my car facing backward.Luckily,there was no one right behind me.I was able to turn my car around and slowly drive on.You see,what had happened was,I ran into a patch of black ice.And the nature of black ice is that you just don’t see it coming because it’s practically invisible.Generally,the formation of ice requires two conditions:the presence of water and temperatures below freezing.However,black ice can form on the highway when the air temperature is slightly above freezing but the ground temperature is below freezing.That’s how it was at seven o’clock this morning when I was driving to campus.The air temperature was 34 degrees Fahrenheit;however,the overnight low had been in the low twenties,so the ground temperature was below freezing.The black ice formed when evaporation on the wet surface of the pavement—it was mist,actually,water vapor—when the mist was exposed to above-freezing air temperatures.The evaporation lowered the surface temperature to below freezing,and this then froze the very thin layer of mist on the surface of the pavement.

M:Excuse me,Dr.West.I’m not sure I heard you correctly.Are you saying it’s possible for ice to form,even when it’s not freezing outside?W:Yes,and black ice is a good example of this.The air temperature can be above freezing,but the temperature of a wet surface like pavement can be lower.The same thing happens when wet laundry is left hanging outside and it freezes solid at an air temperature of 35 degrees.Water evaporates from the wet clothes,which are colder than the air,and the vapor rising from the laundry freezes.So yourclothes arc then covered with a thin film of ice.One of the reasons black ice takes us so much by surprise is that we don’t expect to find ice when the thermometer says it’s above freezing—the air temperature,that is.But air temperature can be deceiving,and we have to be careful,especially on mornings like today.We usually think of ice formation as the freezing of liquid water,but ice can also form by the process of sublimation.Sublimation is when water changes state from a gas directly to a solid—or from a solid to a gas—without first becoming a liquid.Ice formed in this way—by sublimation—forms directly from water vapor,or mist,which is a gas.

M:So,what you’re saying is,black ice is formed by sublimation?

W:Yes.Black ice is formed by sublimation—directly from water vapor on the surface of the road.Black ice is a form of frost.Some other forms of frost are ground frost and the frost you see on windows on cold winter nights.It can look like delicate feathery patterns of crystals on your windowpane,or it can be fernlike crystals several centimeters long on the twigs and branches of trees.Water vapor forms as frost on the surface of an object if the temperature of the surface falls below both the freezing point and the point at which water vapor condenses to a liquid.In the case of window frost,the temperature of the window glass has to be below freezing.The window is chilled because it’s losing heat to the colder air outside.By the way,the beautiful patterns of window frost are due to its slightly curved crystals,because of organic impurities on the glass—dust and dirt—that interfere with crystal growth.

二、The Formation of Ice托福听力中文翻译：

W：我很高兴看到大家今天早上都安全到达学校。我希望我也能对自己说同样的话，但当我上高速公路时，我遇到了一个相当危险的情况。我在入口匝道上，我的车突然打滑，完全转向，所以我的车向后开。幸运的是，我后面没有人。我能够把车调转过来，慢慢地继续行驶。你看，发生的事情是，我撞上了一片黑冰。黑冰的本质是你看不到它的到来，因为它实际上是看不见的。一般来说，冰的形成需要两个条件：水的存在和低于冰点的温度。然而，当气温略高于冰点但地面温度低于冰点时，高速公路上会形成黑冰。今天早上七点，我开车去校园的时候就是这样。气温为34华氏度；然而，夜间的最低气温一直在20多度左右，因此地面温度低于零度。当薄雾暴露在高于冰点的空气温度下时，在潮湿的路面上蒸发形成的黑冰是薄雾，实际上是水蒸气。蒸发使路面温度降至零度以下，然后使路面表面的一层薄薄的薄雾结冰。

M：对不起，韦斯特医生。我不确定我没听错。你是说即使外面没有结冰，也有可能结冰吗？W：是的，黑冰就是一个很好的例子。空气温度可以在冰点以上，但像路面这样的潮湿表面的温度可以更低。当湿衣服挂在外面，在35度的空气温度下固体结冰时，也会发生同样的情况。水从比空气冷的湿衣服中蒸发，从衣服中升起的蒸汽结冰。于是你的衣服就被一层薄薄的冰覆盖了。黑冰让我们如此惊讶的原因之一是，当温度计显示温度高于空气温度时，我们不希望发现冰。但空气温度可能是骗人的，我们必须小心，尤其是在今天这样的早晨。我们通常认为冰的形成是液态水的冻结，但冰也可以通过升华的过程形成。升华是指水在不首先变成液体的情况下从气体直接变成固体或从固体变成气体的状态。通过升华以这种方式形成的冰直接由水蒸气或薄雾形成，这是一种气体。

M：那么，你的意思是，黑冰是由升华形成的？

W：是的。黑冰是由道路表面的水蒸气直接升华而成。黑冰是霜的一种形式。其他一些形式的霜冻是地面霜冻和你在寒冷的冬夜在窗户上看到的霜冻。它可以看起来像你窗格上精致的羽毛状晶体图案，也可以是树枝上几厘米长的蕨类晶体。如果物体表面的温度低于冰点和水蒸气凝结成液体的温度，则水蒸气在物体表面形成霜。在窗户结霜的情况下，窗户玻璃的温度必须低于冰点。窗户被冻僵了，因为它正在向外面较冷的空气散热。顺便说一句，窗霜的美丽图案是由于其轻微弯曲的晶体，因为玻璃灰尘和污垢上的有机杂质会干扰晶体的生长。

三、The Formation of Ice托福听力问题：

Q1:1.What is the talk mainly about?

A.The dangers of driving in icy conditions

B.The formation of ice from water vapor

C.The various colors that ice crystals take

D.The ice that falls to earth as precipitation

Q2:2.Why does the professor talk about her drive to school this morning?

A.To give an example of a safe driving practice

B.To encourage students to tell personal stories

C.To describe the best way to get to campus

D.To lead into the topic of discussion

Q3:3.The professor briefly explains how black ice forms.Indicate whether each sentence below is part of the process.For each sentence,click in the correct box.

Snow changes to ice on tree branches and other exposed surfaces.

The air temperature is above freezing,but the ground temperature is below freezing.

A thin layer of water vapor freezes on the surface of the highway.

Pellets of ice develop from supercooled water droplets.

Q4:4.Why does the professor say this:

A.To warn students not to hang laundry outdoors

B.To find out if the students wash their own clothes

C.To illustrate the same phenomenon in a different way

D.To point out a mystery that scientists cannot explain

Q5:5.Which of the following sentences illustrates sublimation?

A.A thin layer of ice forms on the surface of a lake.

B.Raindrops freeze when they touch the cold ground.