a book is at rest on a table. identify the correct free - body diagram for this situation.
a book is at rest on a table. identify the correct free - body diagram for this situation.
Answer
Explanation:
Step1: Analyze forces on book
The book at rest on the table has two forces acting on it. The force of gravity $F_g$ acts downwards due to Earth's pull, and the normal force $F_N$ exerted by the table acts upwards to balance the force of gravity since the book is in equilibrium. There is no frictional force $F_f$ as there is no relative motion or tendency of relative motion between the book and the table.
Step2: Match with diagrams
The first diagram has both $F_g$ and $F_N$ acting downwards which is incorrect. The second diagram has a frictional force $F_f$ which is not present in this situation. The third diagram has the force of gravity $F_g$ acting downwards and the normal force $F_N$ acting upwards which is correct for a book at rest on a table.
Answer:
The third free - body diagram (with $F_N$ upwards and $F_g$ downwards) is correct.