A book lies at rest on a horizontal wooden table. Your friend gives the book a gentle horizontal push for about 3 s, yet the book does not slide.
a. (i) Define a balanced force.
b. (ii) Draw a neat, labelled free-body diagram for the book before the push and state whether the forces acting on it are balanced or unbalanced.
c. (iii) Draw a similar free-body diagram for the book during the push. Identify the horizontal force that opposes the push.
d. (iv) Explain clearly why the book remains at rest throughout the situation even though a horizontal force is applied.