我们的周围有各种各样的机械,如我们每天吃饭用的筷子(图1a),汽车起重机吊起货物(图1b),准确计时的钟表(图1c)等。各种各样的机械都集中了人类的智慧,不管它是简单还是多么复杂,都可以从中找到构成他们的基本元素——杆、轮、链等。我们物理学就从最简单的机械入手,了解他们是如何帮助我们人类的。 There are all kinds of machines around us, such as the chopsticks we eat every day (Figure 1a), the truck crane to lift the cargo (Figure 1b), the timepiece (Figure 1c) and so on. A great variety of machines have concentrated human wisdom, no matter whether it is simple or complex, from which one can find the basic elements that make up them - poles, wheels, chains and so on. Let’s start with the simplest mechanics in physics and see how they help our humanity.