| F = − | CR + K | − Ra2, |
| M |
(19)
| N | = − | D | = |
| , | ||||
| L | F |
|
(20)
| ( | A | + a2 ) n2 = | (CR + K) | [( | C | + a2 ) R + | K | ] − g (a − ρ). |
| M | A | M | M |
(21)
Thus with K = 0, and rolling with velocity V = Ra, stability requires
| V2 | > | a − ρ | > ½ | A | a − ρ | , | |
| 2g | 2C/A (C/Ma2 + 1) | C | C/Ma2 + 1 |
(22)
or the body must have acquired velocity greater than attained by rolling down a plane through a vertical height ½ (a − ρ) A/C.