Speed and VelocityThe instantaneous velocity is just that, the velocity at a given instant. If we take average velocities over shorter and shorter time intervals, the velocity we find will eventually approach the instantaneous velocity.
Instantaneous Velocity (usually denoted as v) = lim?t->0(?x/?t) = dx/dt (in calculus notation)
- Instantaneous speed (s) = |v|
Typically in physics, we measure speed (and velocity) in quantities like m/s, but in the outside world, other quantities like miles/hour are common. It is important to practice the techniques of unit conversion discussed in chapter two.