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

A 4.00 kg mass and a 3.00 kg mass are attached to opposite ends of a thin 44 cm long horizontal rod (see figure). The system is rotating at angular speed ω = 6 rad/s about a vertical axle at the center of the rod.

(a) Determine the kinetic energy K of the system.

(b) Determine the net force on each mass.

(c) Repeat parts (a) and (b) assuming that the axle passes through the CM of the system.

2. Relevant equations

3. The attempt at a solution

KE=1/2(0.3388m*N)(6rad/s)^2=6.10 J

F1=(4kg)(6rad/s)^2(0.22m)=31.7 N

F2=(3kg)(6rad/s)^2(0.22m)=23.8 N

CM=(4kg)(0.22m)+(3kg)(0.22m)/4kg+3kg=0.22m

How does the CM change the problem? I am having trouble figuring out the second set of answers.

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# Homework Help: Rotational Motion of a thin rod

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