A massless string is wrapped around the equator of a solid sphere (mass M = 76.2 kg, radius R = 0.211 m). A girl holds the free end of the string, and the sphere is released from rest, Assume:(adsbygoogle = window.adsbygoogle || []).push({});

- the sphere is always parallel to the floor

- the string is always perpendicular to the radius of the sphere

- the string does not slip over the sphere

What is the length of the string that has been unwound when the sphere reaches an angular speed ω = 28.6 rad/s?

Can someone please help? Here is what I did but answer is wrong:

v = ωr = 6.0346 m/s

vf^2 = v0^2 + 2as

s = 1.86 m

1.86 = 1/2at^2

t= .615s

.615s * 28.6 = 17.59

17.59 * .211 = 3.7....but this wrong....please help?

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# Homework Help: Rotational Plus Translational Motion for Sphere of Yarn

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