This simple little model bird uses the opposing forces of gravity and a spring to flutter its way down a pole but, as Rob says, watch out for the sharp wire end while you are making it, and stick a ball of plasticine on the wire end to make it safe when you are finished .
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Pecking Bird Model – an exercise in gravity and friction
![1667544072_maxresdefault.jpg](http://petapedia.co.uk/wp-content/uploads/2022/11/1667544072_maxresdefault.jpg)