Transcription: In this demonstration, I want to show you how a block and tackle system can use the mechanical advantage of a pulley. We'll start with a single pulley. So here's our single pulley. On each side of the pulley I have four washers. Let me count them for you. One, two, three, four. One, two, three, four. Okay, now watch what happens when I release these washers. Not very exciting, is it? The washers just hang there. Why? Well, there are four washers on each side of the pulley. Thus, there's equal weight on each side of the pulley. A single pulley offers no mechanical advantage, so neither side of ...
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