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Consider a uniform disc in the x-y plane free to rotate about an axis parallel to the Z-axis as shown (passing through the centre). A force of 4N applied at 4 , 3 along y-axis, as shown produces an angular acceleration of 2 s - 2 . Locate the centre of mass of the disc if the mass of the disc is 2 kg.

Options

  1. A(1, 3)
  2. B(2, 3)
  3. C(0, 3)
  4. D(4, 3)

Correct answer

B. (2, 3)

Step-by-step solution

As τ = I α 4 R = 2 R 2 2   2 ⇒           R = 2   m Thus, COM is at (2, 3)

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