can someone help me with this problem:(adsbygoogle = window.adsbygoogle || []).push({});

"show that a point is travelling along the surface of a sphere if and only if its velocity vector is orthogonal to its position vector."

I know that it is true intuitively - since in centripetal motion, the velocity is always directed toward the center. but how do you prove this using vector calculus?

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# Surface of sphere

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