A uniform sphere made of modeling clay has radius R=0.34m and moment of inertia I=2.77 for rotation about a diameter. It is flattened to a disk with the same radius . What is the moment of inertia of the disk for rotation about an axis that is at the center of the disk and perpendicular to its flat surface?

Respuesta :

Answer:

[tex]I_1 = 3.463\ kg.m^2[/tex]

Explanation:

Given,

Moment of inertia of sphere, I = 2.77

Radius of sphere, R = 0.34

Moment of inertia of sphere

[tex]I = \dfrac{2}{5}MR^2[/tex]

[tex]M= \dfrac{5I}{2R^2}[/tex]

Moment of inertia of disk

[tex]I = \dfrac{1}{2}MR^2[/tex]

Mass of the disk remains same

[tex]I_1 = \dfrac{1}{2}\times \dfrac{5I}{2R^2} \times R^2[/tex]

[tex]I_1 = 1.25I[/tex]

[tex]I_1 = 1.25\times 2.77[/tex]

[tex]I_1 = 3.463\ kg.m^2[/tex]