A thin spherical shell of radius R = 0.50 m and mass 15 kg rotates about the z-axis through its center and parallel to its axis. When the angular velocity is 5.0 rad/s, its angular momentum (in kg ⋅ m2/s) is approximately:
a . 15
L = r x mv
L = Iω
v = rω
Moment of inertia of thin spherical shell = (2/3)mr^2
The Attempt at a Solution
I seem to be getting different answer using the equations above and I can't figure out why.
v = 0.5 * 5 = 2.5
L = (0.5)(15)(2.5) = 18.75
L = (5)(2/3)(15)(0.5)^2 = 12.5
The answer is the first one (18.75) but where did I go wrong with the using L = Iω?