【英语时差8,16】雷雨天的避难所

Cars And Lightning You may have heard that your car is a safe place to be in a thunder storm, and this is true. You might not know the reason for this, however.We’ll learn exactly what would happen if lightning struck your car. At first you might think that the rubber tires would keep you safe. After all, the rubber insulation¹ on appliance cords keeps you from getting shocked every time you plug in a lamp. Unfortunately, the rubber in your tires won’t slow a lightning bolt at all, especially if they’re wet. A lightning bolt has up to a hundred million volts²; once it gets going, it won’t slow down for much. Remember that the lightning already must travel about a mile between cloud and ground and that much air is usually a pretty good insulator³. If the rubber tires won’t keep you safe from a lightning strike, what does? Believe it or not, it’s your car’s metal chassis⁴! Although metal conducts electricity-and might even attract a lightning bolt-you’re protected because of the particular way that electricity moves through metal. When a rapid pulse of electric current moves along a copper⁵ wire, all the current moves across the outer surface of the copper. There isn’t any electrical movement inside the wire itself. The same is true of your car. Although a lightning strike contains a lot of energy, it will all travel along the outer surface of your car, never reaching the interior. The safest place to be in a storm is probably in a house or building with adequate lightning rods, but if a storm happens to catch you while driving,unless there is a tornado⁶, then you should seek safer shelter.

1 insulation   

n.隔离；绝缘；隔热

参考例句：

• Please examine the insulation of the electric wires in my house.请检查一下我屋子里电线的绝缘情况。
• It is always difficult to assure good insulation between the electric leads.要保证两个电触头之间有良好的绝缘总是很困难的。

2 volts   

n.（电压单位）伏特( volt的名词复数 )

参考例句：

• The floating potential, Vf is usually only a few volts below ground. 浮置电势Vf通常只低于接地电位几伏。 来自辞典例句
• If gamma particles are present, potential differences of several thousand volts can be generated. 如果存在γ粒子，可能产生几千伏的电位差。 来自辞典例句

3 insulator   

n.隔离者；绝缘体

参考例句：

• Few substances can equal fur as an insulator.作为绝缘体很少有其他材料能与动物皮毛相媲美。
• A loose mulch acts on the surface as an insulator.疏松的覆盖物在土壤表面起了隔热的作用。

4 chassis   

n.汽车等之底盘；（飞机的）起落架；炮底架

参考例句：

• The new parts may include the sheet metal,the transmission,or the chassis.新部件可能包括钢壳，变速器或底盘。
• Can chassis and whole-vehicle manufacturers co-exist peacefully?底盘企业和整车企业能相安无事吗？

5 copper   

n.铜；铜币；铜器；adj.铜(制)的；(紫)铜色的

参考例句：

• The students are asked to prove the purity of copper.要求学生们检验铜的纯度。
• Copper is a good medium for the conduction of heat and electricity.铜是热和电的良导体。

6 tornado   

n.飓风，龙卷风

参考例句：

• A tornado whirled into the town last week.龙卷风上周袭击了这座城市。
• The approaching tornado struck awe in our hearts.正在逼近的龙卷风使我们惊恐万分。