A charge of 4.30 x 10^-6 C is placed on a small conducting sphere that is located at the end of a thin insulating rod whose length is 0.22m. The rod rotates with an angular speed of w=159 rad/s about an axis that passes perpendicular through its other end. Find the magnetic moment of the rotating charge. (Hint: The charge travels around a circle in a time equal to the period of the motion)

I can not figure this out! The only equation I've found in the book is magnetic moment= NIA. but I'm confused where to go now. Help?

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