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Something with a constant speed can accelerate whilst it's speed stays constant.
That's interesting. How does that work?
That's cool, I love learning the origin of words
Notice I said speed. If an object rotates in circular motion about a fixed point with it's speed constant, it's vector velocity constantly changes as it's direction of motion constantly changes. An acceleration is the rate of change of velocity with respect to time therefore there must be an acceleration. This acceleration is towards the centre of the circle, the object obeys Newton's first law in the sense that it 'tries' to keep moving in a straight line, but there is a net force on that object due to it's mass and acceleration, F=ma. Therefore it moves in a circle because the force is always perpendicular to it's vector velocity and directed towards the centre.