radius of gyration

Question

A body has a moment of inertia of 20 kg·m² and mass 5 kg. What is its radius of gyration?

RankGuru · Accepted Answer

1. **Definition**: Radius of gyration ($k$) is the effective distance from the axis at which the whole mass ($M$) can be considered concentrated to keep $I$ the same.
2. **Formula**: $I = M k^2$.
3. **Transpose**: $k = \sqrt{I/M}$.
4. **Calculation**:
   - $k = \sqrt{20 / 5} = \sqrt{4}$.
5. **Result**: $k = 2$ m.

Rank Guru

radius of gyration

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