A disk 8.0 cm in diameter is initially at rest. A small dot is painted on the edge of the disk. The disk accelerates at [tex]600rad/s^2 [/tex] for .5s, then coasts at a steady angular velocity for another .5s.(adsbygoogle = window.adsbygoogle || []).push({});

What is the speed of the dot at t = 1 s?

Through how many revolutions has it turned?

I approached the first question by drawing a graph of the angular acceleration Vs. time. I then obtained the angular velocity by finding the area under the graph.

I then used the formula V=rwto get the speed.

I obtained 24m/s as my final result.

Is this reasonable?

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# A disk 8.0 cm in diameter is initially at rest. A small dot is painted

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