Question

Calculate the moment of inertia of a copper sphere of diameter 20 cm about a tangent to the sphere
(density of copper = 8.9 g/cm).​

Answer 1

Question :- we have to find moment of inertia of sphere.

Given :- diameter of sphere = 20 cm ,

density of copper = 8.9g/cm³

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we know that ,

Mass = density * Volume

now, we know that volume of sphere = 4/3 πr³

Density = 8.9g/cm³

Mass = 4/3 * π * (10)³ * 8.9 = 37.28 * 10³gm

Now , moment of inertia about a tangent sphere = (2/5mr²) + mr² = 7/5mr²

Putting values we get,

moment of inertia = 7/5 * (37.28*10³gm) * (10)² = $\large\red{\boxed{\sf </strong><strong> </strong><strong>5.22 \times 10^{6} \: </strong><strong>gm\</strong><strong>:</strong><strong>{cm}^{2} }}$

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Answer 2

Answer:

Explanation:

Question :- we have to find moment of inertia of sphere.

Given :- diameter of sphere = 20 cm ,

density of copper = 8.9g/cm³

we know that ,

Mass = density * Volume

now, we know that volume of sphere = 4/3 πr³

Density = 8.9g/cm³

Mass = 4/3 * π * (10)³ * 8.9 = 37.28 * 10³gm

Now , moment of inertia about a tangent sphere = (2/5mr²) + mr² = 7/5mr²

Putting values we get,

moment of inertia = 7/5 * (37.28*10³gm) * (10)² =