Final answer:
Newton's 2nd law is the relationship between mass and acceleration, expressed by F = ma.
Step-by-step explanation:
Newton's 2nd law can be best described as a relationship between mass and acceleration, expressed by the formula F = ma. According to this law, if a mass accelerates, it is the result of a force acting on it. This law is a fundamental principle in physics and helps us understand how forces affect the motion of objects.
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