What does balanced force mean?
Two forces which are equal in magnitude but opposite in directions are called balanced forces.
When two forces which are equal in magnitude but opposite in direction then the system will be at rest. For e.g., When we keep a book on a table two forces act on it:-
1. The upward force which is exerted by the book itself in the upward direction.
2. The force of gravity which is exerted by the the earth on the book in the downward direction.
According to Newton's third law, "For every action there is an equal and opposite reaction". Basically, the gravitational force will pull the book in the the downward direction but to nullify the effect of the force of gravity , the book itself exerts a force which is opposite in direction but equal in magnitude. Therefore, due to these two balanced forces the book remains at rest. So, the book is said to be in the state of equilibrium.