铁锹是一种最简单的普通劳动工具。大概没有人不知道铁锹是什么。但是我敢说,不是每个人都知道铁锹里面的科学。那是在19世纪末,美国有一位学者叫泰勒,他为了弄清楚铁锹的使用效率,从工效学的角度对铁锹进行了研究。他选择了形状相同而铲土量不同的四种铁锹去铲同样一堆煤。这四种铁锹可铲煤的重量分别是5公斤、10公斤、1 7公斤和30公斤。虽然,17公斤和30公斤的铁锹每次铲煤量大于 Shovels are one of the simplest types of ordinary working tools. No one probably does not know what a shovel is. But I dare say that not everyone knows the science inside shovels. That was at the end of the nineteenth century when a scholar in the United States called Taylor. In order to find out the efficiency of shovels, he studied shovels from the perspective of ergonomics. He chose four shovels of the same shape and a different amount of shovel to shovel the same pile of coal. The four shovels shovel coal weighs 5 kg, 10 kg, 17 kg and 30 kg respectively. Although, shovels of 17 kg and 30 kg each shovel coal more than