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A 2.25kg solid sphere has a rotational inertia about its center

• of gravity of 1.52kg.m2. What is the radius of the sphere?

User Sumerz
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1 Answer

8 votes

Answer:

r = 1.3m

Step-by-step explanation:

The moment of inertia of a solid sphere can be expressed using the formula;

I = ⅖ mr²

Where;

I = moment (kgm²)

m = mass of the sphere (kg)

r = rotational radius of the sphere (m)

Based on the provided information in this question, I = 1.52 kgm², m = 2.25 kg, r = ?

1.52 = ⅖ × 2.25 × r²

1.52 = 0.4 × 2.25 × r²

1.52 = 0.9 × r²

1.52 = 0.9r²

r² = 1.52/0.9

r² = 1.688

r² = 1.69

r = √1.69

r = 1.3m

User Macks
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