the radius of a CD is 0.06 m and it rotates at 3.5 rew/ s when playing music at the outer edge.find the maximum tangential speed of the disk.

2 answers

find the circumference ... 2 π r

it goes around 3.5 times in one sec ... in one second, the outer edge travels
... 3.5 circumferences
Circumference = 2pi*r = 6.28 * 0.06 = 0.3768 m/rev.

Speed = 3.5rev/s * 0.3768m/rev = m/s.