A ball balanced on a vertical rod is an example of

A ball balanced on a vertical rod is an example of

  1. stable equilibrium
  2. unstable equilibrium
  3. neutral equilibrium
  4. perfect equilibrium

Answer

There are three states of equilibrium: stable, unstable and neutral.

Stable equilibrium is when the center of gravity of a body lies below point of suspension or support. For example a book lying on a table is in stable equilibrium.

Unstable equilibrium is when the center of gravity of a body lies above the point of suspension or support. 

Neutral equilibrium is when the center of gravity of a body lies at the point of suspension or support. Example: rolling ball.

The correct option is B.