【英语时差8,16】了解暖水瓶的工作原理-下
时间：2019-03-06 作者：英语课 分类：英语时差8，16
英语课
What’s A Good Insulator 1? How about air? Air is, in fact, a pretty good insulator, which is why styrofoam keeps things hot. It’s full of air. But even better than that would be a vacuum. Because there’s nothing in it to heat up, heat can’t conduct through it. A vacuum is the best insulator of all, and that’s the principle behind a thermos 2. A thermos is a flask 3 with a double-walled container inside it. Air is removed from the space in-between the walls. Now heat can’t escape from the soup; it’s surrounded by a vacuum. And to further help hold in heat the inside walls are silvered to reflect heat rays which try to escape.
n.隔离者；绝缘体
- 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。
n.保湿瓶，热水瓶
- Can I borrow your thermos?我可以借用你的暖水瓶吗？
- It's handy to have the thermos here.暖瓶放在这儿好拿。