Q: What is the linear acceleration of a point on the rim of a 30-cm-diameter record rotating at a constant angular speed of 33.5 rev/min?(adsbygoogle = window.adsbygoogle || []).push({});

I seem to have all the variables and equations in hand -

r = .15m and [itex]\omega[/itex] = 3.49 radians/second;

[itex]v = \omega r[/itex] ;

(radial component of linear acceleration) [itex]a_r = \frac {v^2} {r} \omega^2 r[/itex]

...but I get 3.29 [itex]\frac {m} {s^2}[/itex] (pointing inward), and the book's answer is 1.8 [itex]\frac {m} {s^2}[/itex]. Am I wrong? Is the book wrong? Did I just convert something wrong somewhere? I'm very confused.

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# Homework Help: Rotational motion question

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