Experiment with simple machines in this SciGirls activity where students design and create their own moving sculpture. Machines help us get work done; some are complex, with lots of moving parts, and others are simple. Cams are one example of a simple machine. They are like gears, but have no teeth and come in lots of different shapes. We use them to convert rotating motion (such as turning a crank) into back and forth motion (such as waving an arm). You'll find cams in everyday objects such as cars, music boxes, wooden automata, and toys.
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