In an engineering lab, a balancing wheel has two 40 cm rods, each with a 450 g mass at its end, mounted 180° apart on a central axle. The rods are spaced 60 cm apart along the axle, and the setup spins at 4.0 rad/s.
i. Calculate the axial component of the total angular momentum.
ii. Determine the angle between the angular momentum vector and the axle. [Hint: Compute the angular momentum vectors for both masses from a consistent reference point, possibly the center of mass.]

• A. $\text{ i. }0.30\mathrm{~kg}\cdot \mathrm{m}^2/\mathrm{s}\text{, ii. }25^{\circ }$
• B. $\text{ i. }0.48\mathrm{~kg}\cdot \mathrm{m}^2/\mathrm{s}\text{, ii. }31^{\circ }$
• C. $\text{ i. }0.58\mathrm{~kg}\cdot \mathrm{m}^2/\mathrm{s}\text{, ii. }37^{\circ }$
• D. $\text{ i. }0.76\mathrm{~kg}\cdot \mathrm{m}^2/\mathrm{s}\text{, ii. }90^{\circ }$

Answer: (C)