M, a solid cylinder (M=1.99 kg, R=0.133 m) pivots on a thin, fixed, frictionless bearing. A string wrapped around the cylinder pulls downward with a force of F which equals the weight of a 0.830 kg mass, i.e, F=8.142 N. Calculate the angular acceleration of the cylinder.(adsbygoogle = window.adsbygoogle || []).push({});

I tried drawing a free body diagram and setting the forces equal to ma.

F_n- mg-F_t= Ma_y

since a= 0, F_n= Mg + F_t

torque= RF_t sin 90= Ia

RF_t=Ia

I=(1/2)MR^2

F_t= (1/2)MRa

mg-ma=(1/2)MR(a/R)

(1/2M +m)a= mg

a=mg/ (1/2 M=m)

I plugged in my numbers, but I think the equation is wrong. Help?

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# Homework Help: Angular acceleration problem

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