Newton’s law of motion cannot be applicable to the particles moving at

Newton’s law of motion cannot be applicable to the particles moving at a speed comparable to the speed of

light
sound
rocket
bullet train
This question was previously asked in
UPSC CISF-AC-EXE – 2017
Newton’s laws of motion are fundamental principles of classical mechanics. Classical mechanics provides an accurate description of the motion of objects in everyday life. However, these laws break down and are not applicable under certain extreme conditions:
1. When the speed of the object is comparable to the speed of light (approximately 3 x 10^8 m/s). In this regime, motion must be described by Einstein’s theory of special relativity. Relativistic effects like time dilation and length contraction become significant.
2. When the size of the object is very small (atomic or subatomic scales). In this regime, quantum mechanics is required to describe the behavior of particles.

The speed of sound, rockets, and bullet trains are all vastly lower than the speed of light, so classical mechanics (and Newton’s laws) apply accurately to objects moving at these speeds.

– Newton’s laws are part of classical mechanics.
– Classical mechanics is an approximation that works well for macroscopic objects at relatively low speeds.
– It fails when speeds approach the speed of light (requiring relativity) or at very small scales (requiring quantum mechanics).
The speed of light is a fundamental constant in the universe. No object with mass can reach or exceed the speed of light. Particles moving at speeds close to light speed are typically subatomic particles accelerated in particle accelerators.