A body in circular motion has the direction of its velocity along the tangent to the circle at each instant. As the direction of tangent changes every instant, the vector quantity velocity changes every instant. No doubt its speed remains a constant.

Since the direction of velocity changes, as per Newtons 1st law, there must be a force to do that. If we do the vector analysis of velocity at time , at time t + Δt , then we find that vector (v) - vector (v +Δv) points towards the center of the circle along the radius and has a magnitude v²/r Δt.

Thus dv/dt = acceleration = v² /r .

Thus we say that even in a uniform circular motion, the object has an acceleration.

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Displacement and distance covered by the point at the tip of the minute hand....

Number of rotations in 30 minutes = 30. The minute hand comes back to its vertically upward position. So displacement is 0. The physical length of the path ie, distance traveled is 30 * 2 π * 7 cm