Q1. How do we say that body is in motion?
Answers
Answer:
if a body is changing its position with respect to time and with respect to a particular point then it is in motion.
SUPPOSE YOU WILL TAKE A YOUR HOUSE A POINT AND WHEN YOU MOVE YOU ARE CHANGING YOUR POSITION WITH RESPECT TO YOUR HOUSE THAT IS MOTION
Explanation:
A body is said to be in a state of motion when it is moving or equivalently its position continuously changes with respect to time.
OR
Every object in the universe can claim to be in motion.
Every non accelerating object in the universe can claim to be at rest.
Motion is not a property of one body, but a relative state between bodies, all motion less than light speed is relative. (Massless particles can’t have relative motion, their motion is absolute).
”A body is in motion when it changes position over time” - used in junior maths is also a correct statement, coordinates on a graph are measurements of an observer, not intrinsic properties of an object, it seems obvious in a book that the object is moving, but the math is the same if the object is at rest and the graph moves. Both can claim to be at rest at the same time and both are correct, there is no way to prove either wrong. Also, every object has its own graph in which it is not moving, we call that it’s inertial frame.
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