1. Describing Motion
Motion is a change of position with time. It can be Uniform (equal distances in equal
time) or Non-uniform.
- Distance vs Displacement: Distance is total path length (scalar);
Displacement is the shortest path between start and end (vector).
- Speed vs Velocity: Speed is distance/time; Velocity is
displacement/time.
2. Acceleration
The rate of change of velocity is called acceleration (a = (v-u)/t). SI unit: m/s².
3. Equations of Motion
For uniform acceleration:
- v = u + at
- s = ut + ½at²
- 2as = v² - u²
4. Circular Motion
An object moving in a circular path with constant speed is in Uniform Circular Motion.
Its direction changes constantly, so it is an accelerated motion.