Guest

In this problem, we use the result of the previous problem for the rotational inertia of a disk to compute the rotational inertia of a uniform solid sphere of mass M and radius R about an axis through its center. Consider an element dill of the sphere in the form of a disk of thickness dz at a height z above the center (see Fig). (a) Expressed as a fraction of the total mass M, what is the mass dill of the element? (b) Considering the element as a disk, what is its rotational inertia dI? (c) Integrate the result of (b) over the entire sphere to find the rotational inertia of the sphere.

In this problem,  we use the result of the previous problem for the rotational  inertia of a disk to compute the rotational inertia of a uniform  solid sphere of mass M and radius R about an axis through its center. Consider  an element dill of the sphere in the form of a disk of thickness  dz at a height z above the center (see Fig). (a) Expressed  as a fraction of the total mass M, what is the mass dill of the element? (b) Considering the element as a disk, what is its rotational inertia dI? (c) Integrate the result of (b) over the entire sphere to find the rotational inertia of the sphere.

Grade:11

1 Answers

Aditi Chauhan
askIITians Faculty 396 Points
8 years ago
(a) Equate mass per unit volume of the disk and the solid sphere,
236-1695_1.PNG
(b) The rotational inertia of the disk with mass dm and radius r is:

236-2162_1.PNG
(c) Integrate the rotational inertia of the disk under the limit z = - R to z = - R
236-2308_1.PNG

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free