Question

a book is sitting still on your desk. are the forces acting on the book balanced or unbalanced? explain.

Answer 1

They are balanced. If the forces were not balanced the book would move*. In this example, the downward force of gravity on the book is counterbalanced by the upthrust of the desk. 

Answer 2

The answer to this is balanced. Remember the downward force of gravity on the book is counterbalanced by the upthrust of the desk. Note that moving objects can also have balanced forces acting on them. if an object is moving at a constant speed, the force acting on it are balanced. It they are unbalanced the object would either accelerate or decelerate.

Hope this helped.