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AP EAMCET202124 Aug 2021Evening ShiftPhysicsRotational MotionActual

A circular disc is to be made by using equal masses of aluminium and iron. To get maximum moment of inertia, about its geometrical axis, it should be prepared in a way that

Options

  1. Aaluminium is at the interior and the iron surrounding it
  2. Biron is at the interior and the aluminium surrounding it
  3. Caluminium and iron are used in alternate layers
  4. Daluminium and iron discs should be kept one above the other

Correct answer

A. aluminium is at the interior and the iron surrounding it

Step-by-step solution

Since, the moment of inertia depends on the mass distribution of material and distance of mass from the axis of rotation. We know that, the mass density of iron is more than that of aluminium. Therefore to get maximum moment of inertia of composite disc, aluminium should be placed at interior and iron surrounding it.

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