# Homework Help: Physics - Inertia, Angular Acceleration, Torque etc

1. Apr 16, 2007

### thebigbang

1. The problem statement, all variables and given/known data

Part One:

Imagine a hollow sphere of radius R and mass M. It is welded to the end of a solid rod of length L, whose mass is also M. The rod is attached to the sphere in such a way that the whole assembly, when viewed from the side, looks like a lollipop. (That is, the axis of the rod, if extended, would pass through the center of the sphere.) Find the moment of inertia of the assembly about an axis perpendicular to the rod and passing through the rod's other end (the one away from the sphere).

Part Two:

Imagine now that a torque " T " (tao) is applied to the assembly in Problem 1. (about the same axis as described therein). What would the resulting angular acceleration of the assembly be?

(Note: If you were unable to get an expression for Part One, just use " I " for inertia here. Otherwise, sub in your expression from Problem 1, and simply if possible.)

2. Relevant equations

I=mr2 where the two is a square and m is mass, , r being its perpendicular distance from the axis of rotation

torque = Fr where F is the force and r is the distance ...

3. The attempt at a solution

i don't have one yet...

2. Apr 16, 2007

### Staff: Mentor

Last edited by a moderator: May 2, 2017