To solve this problem, we'll use the principle of conservation of energy, considering both the translational and rotational kinetic energies in the system.

Given Data:

• Mass of spherical shell, $M = 13.0 \, \text{kg}$
• Radius of spherical shell, $R = 0.450 \, \text{m}$
• Rotational inertia of pulley, $I = 0.120 \, \text{kg} \cdot \text{m}^2$
• Radius of pulley, $r = 0.120 \, \text{m}$
• Mass of small object, $m = 3.70 \, \text{kg}$
• Distance fallen by the object, $h = 1.25 \, \text{m}$

Approach:

1. Energy Considerations:

   • The initial energy is zero because the system is at rest.
   • As the object falls, gravitational potential energy converts into:
     • Translational kinetic energy of the falling object ($\frac{1}{2} m v^2$)
     • Rotational kinetic energy of the spherical shell ($\frac{1}{2} I_{\text{shell}} \omega_{\text{shell}}^2$)
     • Rotational kinetic energy of the pulley ($\frac{1}{2} I \omega^2$).

2. Moment of Inertia of the Spherical Shell: For a thin spherical shell rotating about an axis through its center, the moment of inertia is: $I_{\text{shell}} = M R^2$

3. Relation Between Linear and Angular Velocities: Since the cord does not slip on the pulley, the linear speed $v$ of the falling object relates to the angular velocities: $v = r \omega$ $v = R \omega_{\text{shell}}$

4. Energy Conservation Equation: The initial potential energy $mgh$ of the falling object will equal the sum of the kinetic energies at the point when it has fallen $h = 1.25 \, \text{m}$: $mgh = \frac{1}{2} m v^2 + \frac{1}{2} I_{\text{shell}} \omega_{\text{shell}}^2 + \frac{1}{2} I \omega^2$ Substitute $\omega = \frac{v}{r}$ and $\omega_{\text{shell}} = \frac{v}{R}$: $mgh = \frac{1}{2} m v^2 + \frac{1}{2} M R^2 \left( \frac{v}{R} \right)^2 + \frac{1}{2} I \left( \frac{v}{r} \right)^2$

5. Simplify and Solve for $v$: Substitute values and simplify the equation to find $v$.

Let me know if you’d like to see the full calculation steps with numerical values plugged in.

Further Exploration:

1. What happens if there is friction on the pulley’s axle?
2. How would the problem change if the spherical shell had a different shape?
3. What would be the impact if the cord had mass?
4. How would we calculate the final speed if the object was initially moving?
5. How does increasing the radius of the pulley affect the speed?

Tip: Always check units to ensure consistency in physics problems involving rotational and translational quantities.