Question

If the forces acting on an object are balanced, then:
(A) The object will be in equilibrium
(B) The object will be in motion
(C) The object will have zero acceleration
(D) The object loses its shape

Answer 1

Hint
According to Newton’s first law of motion, every object remains at rest or in a uniform motion, unless there is external force acting on it. If the forces are balanced, that means there is no net force acting on the body. So, by checking what happens to the object if the net force, we will be able to answer this question.

Complete step by step answer
Given that the forces acting on the object are balanced, the vector sum of all the forces acting on it, that is, the net force is zero.
We already know that, when the forces are balanced, then the object will be in equilibrium. But, we do not know whether the object will be in motion or not. When the net force is zero, the body will not accelerate, but it can have velocity. That means, if the object was already in motion with a velocity, it will continue to be in motion with the same velocity, and if it was at rest, then it will remain in the state of rest. So, we cannot say whether the object will be in motion or not without knowing its previous state. But we have already discussed that if the net force is zero, then the acceleration of the object will be zero. The object can lose its shape also if the forces are balanced, but it depends on the nature of the object. So with the information given, we cannot comment on the change of shape of the object.
Therefore, the correct answers are the options: A, the object will be in equilibrium and B, the object will have zero acceleration.

Note
According to Newton’s second law of motion, we have force, $F = ma$ where $m$ is the mass of the object and $a$ is the acceleration. So, we can get acceleration, $a = \dfrac{F}{m}$. Therefore, we can easily understand that, when the net force is zero, the object does not accelerate.