(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://img232.imageshack.us/img232/4976/physicswe5.jpg [Broken]

total mass of the rod = 4m

m = 0.4kg; b = 0.4m; a = 1.0m

rod is thin

i need to find the mass moment of inertia for the rotating rod relative to z-axis..

2. Relevant equations

(1/12)ML²

3. The attempt at a solution

for the rod which lies on y axis, i could calculate the mass moment of inertia by using the above equation which will lead me to the following answer

(1/12)*2*0.40*0.8² = 0.0427

but what should i do with the other parts of the rod which are parallel with the z-axis?..

or could i apply the following equation?:

(1/24)*M*L²*sin (2φ)

where φ = 45

thx in advance..

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# Homework Help: Mass moment of inertia (angular mass)

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