Describing Motion

Motion is simply a change in position relative to a reference point. We describe the path using distance (total path length) or displacement (shortest straight line between start and end). While speed is distance per unit time, velocity includes both speed and direction.

Acceleration and Graphs

When an object's velocity changes, it accelerates. Motion can be uniform (constant velocity) or non-uniform (accelerating). We can visualize this using distance-time and velocity-time graphs. The area under a velocity-time graph gives the displacement.

Equations of Motion

For uniform acceleration, three key equations govern motion:
1. v = u + at
2. s = ut + ½at²
3. 2as = v² - u²
We also observe uniform circular motion when objects move in a circular path at a constant speed, constantly changing direction.