Moment of force = Fx perpendicular distance from line of action of force to pivot to line of action of force

Is product of force F and the perpendicular distance from pivot to line of action of force

A body in equilibrium, sum of clockwise moment bout pivot = sum of anticlockwise moment bout same pivot

Defined as the point through which whole weight appears to act

Irregular shape --> use experiment
-have 2 seperate points, where pendulum bob is not moving
-draw a dotted line for each point, have a cross where both lines intersect
-draw a 3rd point to check if the cross is the centre of gravity/ balance using a finger to see if it is centre of gravity. It should not tilt (without any external factors such as wind)

Unstable --> cg drops; line of action through its weight lies outside base; moment of its weight bout contact point cause cone to topple

Neutral --> cg remains same height; line of action through its weight and contact force coincide; moment of its weight bout contact point is 0, stays in position to which it is displaced

Stable --> cg rises bfore returning its original height; line of action through its weight still lies within its base; moment of is weight bout contact point cause cone to go back to its original position

Make cg as low as possible so line of action is harder to go out of contact point

Make base area wider so there is more space which the line of action would not go out of base area easily, hence able to tilt it by a larger angle