Motion is a change of position with time, described relative to a reference frame. A book resting on a train has constant position in the train's frame while its position changes in a frame attached to the track. Neither description is complete until the frame and the measured time have been specified.
A record of successive positions gives a trajectory. Comparing nearby measurements gives velocity, and changes of velocity give acceleration. A camera recording a rolling ball at known time intervals provides a simple measurement: unequal gaps between successive images reveal a changing speed. The description of this record is kinematics; explaining the change using forces belongs to particle dynamics.
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Motion refers to the change in position of an object over time. It is a fundamental concept in physics and can be described in terms of displacement, distance, velocity, acceleration, and time. Motion occurs when an object moves from one location to another, and it can be classified in various ways, including: 1. **Types of Motion**: - **Linear Motion**: Movement in a straight line. - **Rotational Motion**: Movement around an axis or center point.