An airplane propeller is 1.99 m in length (from tip to tip) with
mass 93.0 kg and is rotating at 2500 rpm (rev/min) about an axis
through its center. You can model the propeller as a slender
rod.
What is its rotational kinetic energy?
Suppose that, due to weight constraints, you had to reduce the
propeller's mass to 75.0% of its original mass, but you still
needed to keep the same size and kinetic energy. What would its
angular speed...