Mission F2D3 Equilibrium Concepts
Hold down the T key for 3 seconds to activate the audio accessibility mode, at which point you can click the K key to pause and resume audio. Useful for the Check Your Understanding and See Answers.
Which of the following descriptions COULD be true of an object which is at equilibrium? List all that apply ...
Definition of Equilibrium:
Equilibrium is the condition in which all the individual forces acting upon an object are balanced.
Perhaps the most important word in this question is the word COULD. The presence of this word makes all the difference between which answers you choose and which you eliminate. Because of the word COULD, any choice that could ever be true of an object at equilibrium under some unique condition is an answer. Even if that particular choice is not always true or seldom true, it is an answer to this COULD be true question if it is possible for it to be true.
If an object is at equilibrium, then the individual forces acting upon the object are balanced. Thus, there is no unbalanced force - the net force is 0 Newton. Given this as the definition, one can apply Newton's second law of motion and confidently state that the object is not accelerating. If not accelerating, the velocity is constant. While we do not know for certain what the velocity value is, we do know that it is a constant, unchanging value. It could be 0 m/s in which case the object is at rest and staying at rest. Or it could be 4 m/s, south in which case the object is moving and will continue moving with this speed (4 m/s) and in this direction (south).
