Physics Forces Simulation
Interactive demonstration of Newton's First Law: Objects at rest stay at rest and objects in motion stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Book Forces
Physics Explanation
The book is at rest on a horizontal surface. It is subject to two external forces: the force due to gravity (its weight W) acting downward and the upward normal force R from the table. Since the book is observed to be at rest, the net external force on it must be zero according to Newton's First Law. This implies that the normal force R must be equal and opposite to the weight W.
Key Concept: Since the book is at rest, the net force = 0, therefore R = W.
