Given a solid bowl (an idealized hemisphere, the opening facing straight up), let a slender rod rest in the bowl supported at two points: a point on the bowl's edge, and some point on the bowl's interior surface.

The bowl's edge exerts a force on the rod which is perpendicular to the rod's length.

The bowl's interior exerts, on the rod's end, a force which is perpendicular to the bowl's surface (at the point where they meet).

If the rod's length is three times the radius of the bowl, what is the angle between the rod, and the plane of the bowl's edge?

(In reply to FBD by nikki)

Brilliant and excellent, nikki!   And thank you, since I was not looking forward to working through it all again.

One of my favorite things about math is the way there can be more than one method for arriving at a solution.   One way may be much easier to do.  But sometimes it's about the journey, not just the destination.

Posted by Larry on 2005-01-06 22:12:45