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AP EAMCET202123 Aug 2021Morning ShiftPhysicsRotational MotionActual

Three point-masses m₁, m₂ and m₃ are located at the vertices of an equilateral triangle, having each side of length L . The moment of inertia of the system about an axis along an altitude of the triangle passing through m₁ is given by

Options

  1. AI= (m₁+m₂+m₃ ) L^2
  2. BI= (m₁+m₂ ) L^2 2
  3. CI= (m₂+m₃ ) L^2
  4. DI= (m₂+m₃ ) L^2 4

Correct answer

D. I= (m₂+m₃ ) L^2 4

Step-by-step solution

The given situation is shown below We know that moment of inertia be I=m d^2 where, d is the perpendicular distance between body and axis of rotation, aligned I & =m₂ ( L 2 )^2+m₃ ( L 2 )^2 & = m₂ L^2 4 + m₃ L^2 4 = (m₂+m₃ ) L^2 4 aligned

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