The rod is used to represent a
massless rod with point masses at the ends. Find the angular
momentum for each point mass and clip the pointers on to show the
direction of L. As
the rod rotates, the direction of L changes.
This shows that:
1. L is not necessarily in
the
direction of ω
.
2. L is changing and
therefore requires a torque, which one can feel in rotating the
system. The system is not balanced. (The "feel" comes
because the rod and arrows have mass.)
