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3. A body is said to be at rest if it does not change its position with respect to the reference point
4. Motion means change of position with time. A body is said to be in motion when it's position changes continuously with respect to a stationary object taken as reference point.
5. Motion in One Direction. Motion is the displacement of an object from one place to another in time and space.
6.Displacement (symbolized d or s ), also called length or distance, is a one-dimensional quantity representing the separation between two defined points. The standard unit of displacement in the International System of Units ( SI ) is the meter (m). Displacement is usually measured or defined along a straight line.
7. Distance is a scalar quantity that refers to "how much ground an object has covered" during its motion. Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.