A .22kg , .22-m-diameter plastic disk is spun on an axle through its center by an electric motor. What torque must the motor supply to take the disk from 0 to 1500 rpm in 5.00 ?(adsbygoogle = window.adsbygoogle || []).push({});

I used the equations

T(thau)=alpha/I

w_f=w_i + alpha*(t_f - t_i)

I found I to be equal to .021kgm^2

then found w_f for the first .5s to be:

(1500rev/1min) * (1min/60s) *(2pi/1rev) = 157.08rad/s

157.08=0+alpha*(.5s)

alpha = 31.42rad/s^2

T= 31.42/.021 = 1496.2Nm

Am not totally sure of my calculations. I will greatly appreciate any help

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# Homework Help: A disk accelerates

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