what is stability

Stability is the difficulty with which a body topples.
When a body is at rest, it is said to be in a state of equilibrium or stability.

Types or states of stability or Equilibrium
Some bodies are in a more stable state than others.

There are three types or states of equilibrium or stability:
a) stable equilibrium
b) unstable equilibrium
c) neutral equilibrium

(a) Stable equilibrium:
Is the type of equilibrium where, if the body is slightly tilted and then released:
(i) the centre of gravity of the body is raised.
(ii) the body returns to its original position.

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(b) Unstable equilibrium:
Is the type of equilibrium where, if the body is slightly tilted and then released:
(i) the centre of gravity of the body is lowered.
(ii) the body moves farther away from its original position.

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(c) Neutral equilibrium:
Is the type of equilibrium where, if the body is slightly tilted and then released:
(i) the centre of gravity of the body is neither raised nor lowered.
(ii) the body stays in its new position or it just rolls on before stopping.

Example:
A ball on a flat surface.

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How to increase the stability of a body.
The stability of a body can be increases by:
(i) Lowering the centre of gravity by putting more weight at the base.
(ii) Increasing the area of the base.
(iii) If the body is slightly displaced and then released.

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