A particle moves along a circular path of radius r with constant speed v. Its acceleration is: MCQ with Answer and Explanation

A particle moves along a circular path of radius r with constant speed v. Its acceleration is:
A. v/r directed tangentially
B. v²/r directed away from center
C. v²/r directed towards center
D. Zero
Answer: Option C
Solution (By JKSSB Mock Tests)
In uniform circular motion, speed is constant but velocity direction changes continuously, producing centripetal acceleration. Magnitude a = v²/r, direction always towards the center of the circle. This acceleration changes velocity direction without altering speed. Tangential acceleration would change speed, but here speed is constant. Formula derivation: From vector analysis of velocity change over small time interval. Exam tip: Remember 'centripetal' means 'center-seeking'; this concept is fundamental for rotational dynamics questions in competitive exams.

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