STATICS Centre of mass, Centre of gravity and stability. CENTRE OF MASS
The centre of mass of a body is the point about which its mass can be considered to act. In a body of uniform density and shape, the centre of mass will be at the centre of the shape. If the line of force of a force applied to a body does not pass through the centre of mass then the object will rotate when it moves. It will rotate however about the centre of mass, which itself will move in a straight line.
CENTRE OF GRAVITY
The centre of gravity of a body, is the point at which its entire weight can be considered to act.
In most common circumstances the centre of gravity and centre of mass can be considered to be in the same place. They will
be different if the gravity field is different at differents points in the object.
STABILITY
There are 3 types of equilibrium an object can be in
| A Stable equilibrium | Returns to equilibrium postion when slightly displaced. |
| B Unstable equilibrium | Neither returns to same equilibrium or stays in place when displaced slightly. |
| C Neutral equilibrium | Remains in displaced position when disturbed. |
