A book sitting on a tall shelf demonstrates what kind of energy?

The book sitting on a tall shelf demonstrates potential energy, which is the energy stored in an object due to its position or height. In this case, the book is elevated above the ground, and because of gravity, it has the potential to fall if it were to be pushed or knocked off the shelf. This stored energy is dependent on the height of the book relative to the ground and its mass. The greater the height and the more mass the book has, the more potential energy it will possess.

The other types of energy mentioned—mechanical, kinetic, and chemical—do not accurately describe the situation of the book on the shelf. Mechanical energy refers to the total energy of an object due to its motion and position, kinetic energy is the energy of an object in motion, and chemical energy pertains to the energy stored in the bonds of chemical compounds. Since the book is not moving and is simply at rest on the shelf, potential energy is the most applicable form of energy in this context.