Question

a book is at rest on a table. identify the correct free - body diagram for this situation.

Explanation:

Step1: Analyze forces on the book

A book at rest on a table has two forces: gravitational force (\(F_g\)) downward and normal force (\(F_N\)) upward from the table. These forces are equal in magnitude (since the book is in equilibrium, net force \(F_{net}=0\)) and opposite in direction, acting on the same object (the book).

Step2: Evaluate each diagram

• First diagram: Forces act on the same object (the dot representing the book), equal in length (magnitude) and opposite in direction. This matches the equilibrium condition.
• Second diagram: Forces seem to act on different points (or the upward force is not on the book? The dot for the upward force is above, while the downward is below, suggesting different objects, which is incorrect as both forces act on the book).
• Third diagram: The lengths of the force vectors might not be equal (or the representation is inconsistent), and the key is that for equilibrium, the two forces on the book (gravity and normal) must be equal and opposite, acting on the book. The first diagram correctly shows two forces on the book, equal in magnitude (same length) and opposite in direction.

Answer:

The first free - body diagram (the left - most one) is correct. (Assuming the first diagram has the two force vectors (upward normal and downward gravity) acting on the same point (the book) with equal magnitude (same length) and opposite direction)