I have a question that hours of internet research have not answered. I noticed that, for example, when I am holding a pencil by the eraser end and I let gravity hold it in a vertical position, when i move my hand back and forth, the tip of the pencil lags behind then forms a pendulum with that new angle. What i am looking for is, on a cartesian plane, if given the x and y coordinates of the eraser end of the pencil and the velocity at which that end is moving, if there is an equation to calculate the new angle formed.(adsbygoogle = window.adsbygoogle || []).push({});

Thanks!

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# Moving Pendulum

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