paddlewheel
/ˈpædlwiːl/a large wheel fitted with paddles and driven by an engine in order to propel a boat
noun [专属名词] 桨轮；明轮
It's a trivial matter, by looking at what is the weight and how far does it drop, to say OK, how much work is done by the paddlewheel. 这是一个很简单的问题，通过观察重量是多少以及它下降了多远，来确定桨轮做了多少功。
