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How does a table push upward on a book resting on it?

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A diagram of a cylindrical vessel containing gas, with a movable piston held down by a weight. Countless small dots beneath the piston represent gas particles in rapid, random motion, illustrating Bernoulli's model of gas pressure. — physics As conceived by Daniel Bernoulli in *Hydrodynamica* (1738), gases consist of numerous particles in rapid random motion. He assumed that the pressure of a gas is produced by the direct impact of the particles on the walls of the container.

When a book rests on a table, the table exerts an upward force on the book that is equal and opposite to the downward force of gravity. This upward force is a real physical force rather than a theoretical abstraction.1

The mechanism behind this interaction involves the physical properties of the table's surface. The weight of the book causes the surface of the table to undergo a slight deformation, similar to how a coiled spring compresses under a load. Because of this deformation, the table exerts an upward force on the book to resist the weight pressing down upon it.1

This interaction is governed by Newton’s third law of motion, which states that for every action, there is an equal and opposite reaction. The book exerts a downward force on the table, and the table exerts an equal and opposite upward force on the book. These two forces constitute an action-reaction pair acting on different bodies. Meanwhile, the upward force from the table and the downward force of gravity acting on the book are balanced, resulting in the book remaining in a state of equilibrium.1