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NATURE.M
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Homework Statement
A solid flywheel of radius R and mass M is mounted on a light shaft of radius r so that the axis of rotation is horizontal. A light, inelastic rope is wound around the drive shaft and is connected, via a light, frictionless pulley to a mass m, which is suspended a height h above the floor. You can assume the moment of inertia of the fly wheel is I=1/2MR^2.
(a) If the mass is released from rest and allowed to fall to the floor, find an expression for the final angular velocity of the flywheel.
Homework Equations
So for mass m, I have T[itex]_{1}[/itex]-mg=-ma.
Now I'm not sure if I should assume the mass of the pulley is negligible (the question indicates
light, so I'm not sure).
But assuming its massless, I have the torque τ=-Iσ=-T[itex]_{1}[/itex]r, where σ is the angular acceleration, and clockwise is negative.
Then, since the tension in the rope isn't changing, we have constant σ. So, σ=ω/t. Then since I=1/2MR^2, we have ω = 2mr(g-a)t/MR[itex]^{2}[/itex]
This seems way to cumbersome, any ideas on what I did wrong?
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