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Cam design for high-speed engines: Choose suitable follower motion law. Objective: Minimise shock/jerk and ensure smooth acceleration at high speeds in cam-follower systems. Select the most appropriate follower motion.

Difficulty: Easy

Uniform velocity motion
Simple harmonic motion
Uniform acceleration and retardation
Cycloidal motion
Parabolic motion

Correct Answer: Cycloidal motion

Explanation:

Concept
Cycloidal motion provides zero jerk at the start and end of stroke (continuous acceleration profile), making it ideal for high-speed cams where dynamic forces must be minimised.

Why not others?
Uniform velocity and SHM introduce higher jerk; uniform acceleration/retardation has jerk discontinuities at segment junctions.

Final Answer
Cycloidal motion

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