【单选题】A student sit on a stool (凳子) that can rotate freely about a vertical axis. The student, initially at rest, is holding a bicycle wheel whose rim (边缘) is loaded (装填) with lead (铅) and whose rotational ...
A.
ω b = 2.4rev/s, counterclockwise seen from overhead
B.
ω b = 1.4rev/s, clockwise seen from overhead
C.
ω b = 1.4rev/s, counterclockwise seen from overhead