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GATE 2018 ME (ME2) – Question 42

Theory of Machines · Cams · 2 marks · Multiple choice

A cam follower rises by h while the cam rotates through δ radians at constant angular velocity ω. The follower accelerates uniformly for the first half of the rise and decelerates uniformly for the second half, with equal magnitudes. Find maximum follower velocity.

  1. $4h\omega/\delta$
  2. $h\omega$
  3. $2h\omega/\delta$
  4. $2h\omega$

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Show answer and explanation

Correct answer: (C) $2h\omega/\delta$

Explanation

The rise lasts $t_r=\delta/\omega$. Equal acceleration and deceleration produce a triangular velocity–time graph. Its area is displacement: $h=\tfrac12t_rv_{\max}$. Thus $v_{\max}=2h\omega/\delta$: **C**.