It depends on your frame of reference.
* Relative Motion: Motion is always relative. An object can be at rest relative to one thing, but in motion relative to something else.
* Example: You are sitting in a chair (at rest relative to the chair). But, you are moving at a very high speed relative to the sun!
* Frames of Reference: A frame of reference is simply a perspective from which you are observing motion. It's like choosing a "measuring stick" for motion.
* Example: You're sitting on a train, and a person walks down the aisle. From your frame of reference (on the train), the person is moving. From a frame of reference outside the train, the person is moving at the train's speed plus the speed of their walk.
Key Points:
* Absolute rest is tricky: There's no truly fixed point in the universe to say something is absolutely at rest. Even the Earth, which seems still, is moving in many ways (rotating, orbiting the Sun, etc.).
* Motion is about change in position: The key concept is that motion is about a change in position over time, relative to some other point.
So, to answer your question directly: An object can be at rest relative to one frame of reference and in motion relative to another frame of reference at the same time. It all depends on how you define "at rest" and "in motion."
