Average acceleration is defined as the change in velocity divided by the time taken. For a particle moving in a circle with constant speed, the velocity vector changes direction continuously. Over half a circle, the initial and final velocity vectors are in opposite directions.
A particle is moving in a circle of radius R with a constant speed v. Its average acceleration over the time when it moves over half the circle is :
Asked in UPSC NDA 1 2023 · Topic: Mechanics (Newton's Laws of Motion and their applications)
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