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

A disk of massM1 = 350 gand radiusR1 = 10 cmrotates about its symmetry axis atf_initial = 152 rpm. A second disk of massM2 = 258 gand radiusR2 = 5 cm, initially not rotating, is dropped on top of the first. Frictional forces act to bring the two disks to a common rotational speed f_final.

a)What isf_final? Please give your answer in units of rpm, but do not enter the units

2. Relevant equations

T = I*a

I = (m*r^{2})/2

3. The attempt at a solution

I found the moment of inertia of M1

I = (.5)(.35)(.1^{2}) = .00175 kg*m^{2}

M2

I = (.5)(.258)(.05^{2}) = .0003225 kg*m^{2}

I found the angular velocity [tex]\omega[/tex]

152rpm = 304pi rads/min = 5.06pi rads/sec

I don't suppose that I can just consider the mass to have just increased can I, because it specifies friction. I know some numbers, but how to put them together?

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# Homework Help: Double Rotating disks

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