Simple Machines

Simple Machines. Written by Robert Charles. Illustrated by Randy Gates.

简单机械。 文 / 罗伯特·查尔斯 图 / 兰迪·盖茨

There are many kinds of machines. Most machines make doing work easier. They do this by reducing how much push or pull is needed to do work. Some machines are simple. They have very few parts. They are called simple machines.

机械有很多种。 大多数机械都能让干活变得更轻松。 它们靠减少做功所需的推力或者拉力的大小来实现这一点。 有些机械结构很简单。 它们的零部件非常少。 这类机械叫做简单机械。

A lever is one kind of simple machine. It makes work much easier. A bottle opener is a lever. It makes it easier to open a bottle.

杠杆是简单机械的一种。 它能让干活轻松很多。 开瓶器就是一种杠杆。 用它开瓶子会更省力。

A hammer is a lever too. It makes it easier to pound nails into wood.

锤子也是一种杠杆。 用它把钉子钉进木头里更省力。

An inclined plane is another kind of simple machine. It makes work much easier. The ramp is an inclined plane. It makes it easier to move things into a truck.

斜面是另一种简单机械。 它能让干活轻松很多。 坡道就是一种斜面。 用它把东西搬上卡车会更省力。

The inclined plane uses less force than lifting things straight up and into the truck. But with the inclined plane, you have to move things a greater distance.

和直接把东西抬上卡车相比，用斜面需要的力气更小。 不过用斜面的话，你得把东西多移动一段距离。