Question

Show the rest and motion are both relative and absolute rest or absolute motion is not possible

Answer 1

This proof is rather intuitive, and can be shown through considering any motion in a thought experiment. Imagine a car moving a very fast speed. Every time you do this, your mind automatically conjures the static background against which the startling velocity of the vehicle is compared. And right there creeps in the concept of relativity, that every time you need to conceptualize any motion of a body, you'll have to do this relative to another body. Now, the reference body may or may not be static and there is no way to know for sure. That is because the observer may be moving at equal velocity as that of the reference. Hence, there is no way to determine absolute rest or motion.