Final answer:
Newton's first law of motion is also known as the law of inertia. It states that an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and in the same direction unless acted upon by an external force.
Step-by-step explanation:
Newton's first law of motion is also known as the law of inertia. Inertia refers to the tendency of an object to resist changes in its motion. According to this law, an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and in the same direction unless acted upon by an external force.
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