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Question
Give an example of motion in which speed remains uniform, but the velocity changes.
Solution
Direction of velocity in uniform circular motion
A particle travelling anticlockwise in a circular path with a constant speed v in a horizontal plane. The particle travels in the same amount of time (t = T/4) across each quarter of circles AB, BC, CD, and DA, where T is the particle's round-trip time on the circular path. Particle speed is therefore constant. However, at various places throughout the circular course, the particle's force direction of motion varies.
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