Final answer:
The idealization of a particle in terms of classical mechanics is accurately represented by Newton's laws of motion. These laws hold true for objects moving significantly slower than light and larger than most molecules, while quantum mechanics and Einstein's theory of relativity take precedence at higher speeds and gravitational fields.
Step-by-step explanation:
Another way of discussing the idealization of a particle is in terms of classical mechanics. Classical mechanics is well-explained by Newton's laws of motion, which provide a good approximation to motion under the conditions where objects are moving at speeds much less than the speed of light and are larger than the size of most molecules, approximately 10-9 m in diameter. Once objects are moving at high speeds, close to the speed of light, or in the presence of strong gravitational fields, the theories of quantum mechanics and Einstein's theory of relativity are more appropriate to describe their behaviors.