According to newton’s first law of motion, when will an object at rest begin to move?

a. when its inertia decreases to zero

b. when an unbalanced force acts upon it

c. when the action and reaction forces are equal

d. when two equal and opposite forces act upon it

The correct answer is B. When an unbalanced force acts upon it

Explanation:

Isaac Newton (1642-1726/7) was an important physicist mainly known for this works in classical mechanics and for proposing the law of motion called Newton's laws. In these, there are three main laws that focus on motion and possible forces that act in a body. In the case of the first law, this law states objects that are static or at rest will remain in the same state except if there is an unbalanced force that acts over it, in the same way, an object moves at the same velocity except if there is an unbalance forced acting over ti. Thus, an object at rest begins to move "when an unbalanced force acts upon it".

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