How
fast or at what
speed a particle or point is
moving at a given instant. Also called,
velocity.
Velocity at any instant is obtained from the average velocity by shrinking the time interval t between the minimum speed and maximum speed until it infinitely approaches 0. As t shrinks, the average velocity approaches a limiting value, which is the velocity at that instant.
v = lim t->0 (x/t) = dx/dt