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

I have a motor, with an armature that has a mass of 250kg , and a diameter of 30 cm. Assuming the mass of the armature is evenly distributed, the rotational inertia of the armature is 22.5 kg-m^2.

Now the motor accelerating unloaded, with armature current regulated so that the armature develops a constant torque of 120 N-m, would be coming up to speed at 35.8 rad/sec^2? (Did I get this wrong?)

Assume the torque stays the same, How long will it take for the unloaded armature to accelerate from 0 to 3000 rpm.

2. Relevant equations

T=Ia 22.5 kg-m^2(3000(pie)-15cm(pie))/(T)

22.5(3000(pie)-.15m(pie))/(T)

I think I am doing something wrong here cause I get stuck here.

3. The attempt at a solution

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# Homework Help: Angular acceleration of a motor

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