Answer: F = ma, where F (force) and A (acceleration) are both vector quantities. If a body has a net force acting on it, it is accelerated following the equation. Conversely, if a body is not accelerated, there is no net force acting on it.
Step-by-step explanation:
Putting Newton's 1st law of motion in simple words, a body will not start moving until and unless an external force acts on it. Once it is set in motion, it will not stop or change its velocity until and unless some force acts upon it once more. The first law of motion is sometimes also known as the law of inertia.