| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Specify the moment of inertia of the rolling object.
Tip: First derive an expression for the moment of inertia starting from the principle of energy. Then take advantage of the steadily accelerating motion formulas.
Answer: $0{,}000021\ kgm^2$