Final answer:
An observer in a non-inertial (accelerating) reference frame could experience an apparent violation of Newton's first law of motion. This is because although the object might seem to be moving in a curved path or changing speed in the observer's reference frame, from an inertial reference frame, the object would still be obeying Newton's first law.
Step-by-step explanation:
The subject of this question is Newton's first law of motion, which states that an object will remain at rest or move along a straight line at constant speed, unless acted upon by a net external force. This law is also referred to as the law of inertia. Now, the main answer to your question is that any observer in a non-inertial (accelerating) reference frame could perceive an apparent violation of Newton's first law of motion.
For example, imagine you're in a car that's accelerating. If you roll a ball down the aisle of the car, to you, the ball seems to curve and not move in a straight line, seeming to violate Newton's first law. However, to an observer standing on the street (an inertial reference frame), the ball is moving in a straight line. It's the car (and you with it) that's moving, not the ball. This is a case where our perceptions can give us misconceptions about the physical world.
In conclusion, occurrences of apparent violation of Newton's first law are essentially due to the objects being observed from a non-inertial reference frame where the observer and/or the setting is undergoing acceleration or deceleration.
Learn more about Newton's first law