A book remains at rest on a table because of the balance of forces acting on it, specifically the force of gravity and the normal force.

To elaborate, the reason the book stays at rest on the table can be explained by Newton’s First Law of Motion, often referred to as the Law of Inertia. This law states that an object at rest will remain at rest, and an object in motion will continue in motion, unless acted upon by an external force. In the scenario of the book, there are two primary forces at play: the gravitational force pulling it downward and the normal force exerted by the table pushing it upward.

The gravitational force is determined by the mass of the book and the acceleration due to gravity, which pulls the book toward the center of the Earth. Conversely, the normal force is the force that a surface exerts to support the weight of an object resting upon it; it acts perpendicular to the surface, pushing upward in this case.

When the book is resting on the table, these two forces are in equilibrium, meaning they are equal in magnitude but opposite in direction. This balance results in a net force of zero. According to Newton’s First Law, since the net force acting on the book is zero, the book will remain at rest.

It is also important to note that if an external force, such as a push or pull, were applied to the book, it would begin to move. This motion would continue until another force, such as friction or a hand stopping it, acted upon it to restore equilibrium.

In summary, the book remains at rest on the table due to the balance of forces acting on it: the downward gravitational force is counteracted by the upward normal force from the table. This results in a net force of zero, thereby maintaining the book’s state of rest.