Final answer:
Newton’s first law, also known as the law of inertia, is true in all reference frames. This law states that an object will remain at rest or continue moving with a constant velocity in a straight line, unless acted upon by an unbalanced force.
Step-by-step explanation:
Newton’s first law, also known as the law of inertia, is true in all reference frames. This law states that an object will stay at rest or continue moving with a constant velocity in a straight line, unless acted upon by an unbalanced force. It is important to note that the concept of force and motion are relative to different observers in different reference frames.
For example, let's consider a person sitting in a moving train and observing a ball on the floor. From their frame of reference, the ball appears to be at rest. However, to an observer outside the train, the ball is actually moving because both the train and the ball are in motion.
Newton's first law is valid in all reference frames because it describes the fundamental relationship between forces and motion, regardless of the observer's perspective.
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