Centres of Mass and Stability (AQA A-Level Further Maths): Flashcards

No net motion; all forces and couples balanced

All forces lie in the same plane

Resultant of all forces = 0 (no linear movement)

Total moment = 0 (no rotational movement)

Perpendicular to surface only; no friction

Both normal reaction and friction forces

Where unknown forces act (eliminates them from equation)

$|\mathbf{a}||\mathbf{b}|\sin\theta \, \mathbf{n}$

$\mathbf{M} = \mathbf{r} \times \mathbf{F}$

Resultant force = 0, but total moment ≠ 0