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The air-cushioned vehicle is not an airplane, since it does not have wings.It is neither a ship nor an automobile1, since it travels clear of sea and land.It has a conventional gasoline engine, but no wheels.How does it travel?What keeps it in the air? Under the air car is an air chamber2 with a large propeller3 parallel to the ground.The gasoline engine supplies power that causes the propeller to whirl.This fills the chamber with air.Some of the air is forced toward the ground through tiny holes around the edges of the car. These air jets create a wall that keeps the air from escaping from the chamber.As more and more air crowds into the chamber, the molecules4 of air become compressed.Their pressure becomes so strong that it lifts the car off the ground. Once the car is floating, the driver releases some of the compressed air.This makes the car speed forward. 气垫船不是飞机,因为它没有双翼。它不是轮船,也不是汽车,因为它脱离海面和陆地行驶。气垫船装有常规的汽油发动机,但没有轮子。它是怎样行驶的呢?是什么使它悬在空中的呢? 气垫船下面是一个空气箱,里面装有一个与地面平行的大螺旋桨。汽油发动机供能后,螺旋桨便旋转起来,这就使气箱内布满了空气。部分空气通过气垫船边缘的小孔被压向地面。 这些喷射出的气流形成一道屏障,阻止空气从气箱逸出。由于越来越多的空气聚集在气箱内,空气分子受到压缩。正是这些空气分子的强大压力使汽垫船脱离地面。 当汽垫船浮动时,司机释放出一部分压缩空气,使汽垫船高速向前飞行。 点击收听单词发音
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