Final answer:
Newton's first law of motion, known as the law of inertia, essentially states that an object will remain in its current state of motion unless acted upon by a net external force. Newton's second law quantifies this concept, mathematically expressing the relationship between force, mass, and acceleration with the equation F=ma.
Step-by-step explanation:
The correct statement about Newton's first law of motion is that it explains the relationship between motion and force. This law, also known as the law of inertia, states that an object at rest stays at rest and an object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. To better understand this, we know from Newton's second law that this force can be quantified and we're able to calculate the effects of these forces on an object's motion. More specifically, Newton's second law provides a more quantitative definition, stating the cause and effect relationship between force and changes in motion, mathematically expressed as F=ma, where F represents force, m represents mass, and a represents acceleration. This law is fundamental in physics because it allows the precise calculation of what happens in situations when an external force is applied to an object.