If an object is tied to a string in vertical circular motion (yes, I mean vertical as in the string has the force of gravity acting on it), does it actually change speed? I was given a question where the 'average speed' of an object in vertical circular motion was 6.1 m/s, and then they wanted me to find the point of least speed. So I guess speed changes then? But why? I was taught that the speed of an object in circular motion is always the same but the object is accelerating because direction changes. Does this ONLY apply to horizontal circular motion?