On a warm spring morning 40 years ago, I was moving a wheelbarrow full of sand to mix some mortar. My boss announced in a humorously exasperated way, “hold it, hold it, hold it.” He saw that I was ...

levers use mechanical advantage to make lifting or applying pressure easier the three main parts of a lever are the effort (input force), fulcrum (pivot point), and load (output force) there are three ...