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## Homework Statement

hi again ,, help me to get moment of inertia

A solid sphere, of mass 1.5 kg and radius 5 cm, is connected to the end of a vertical rod

along a y–axis, of mass 2 kg and length 35 cm. The rod can rotate about z–axis passing

through the other end, as show in the figure.

a) What is the moment of inertia of the system (sphere + rod) about z–axis?

b) Starting from rest, the system rotates clockwise around the z–axis from the initial

vertical orientation, what is its angular speed when it is inverted?

## Homework Equations

The moment of inertia about the center of mass:

Irod = ML^2/12 and Isphere = (2/5)mR^2

## The Attempt at a Solution

i tried to solve (I still don't how to get moment of inertia yet) like this :

I=Irod + m(L/2)^2 + (2/5)mR^2+m(LR)^2 = (1/3)ML^2+(7/5)mR^2 is it right ??