The mass of a disc is 700 gm and its radius of gyration is 20 cm. What is its moment of inertia if it rotates about an axis passing through its centre and perpendicular to the face of the disc?

Explanation

To find the moment of inertia (I) of a disc rotating about an axis passing through its center and perpendicular to its face, we can use the formula that relates the moment of inertia to the mass (m) and the radius of gyration (k):

\[ I = m \cdot k^2 \]

### Step-by-Step Solution:

**Step 1: Convert mass from grams to kilograms.**
- Given mass of the disc is 700 grams.
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