How do you measure instantaneous speed??

Instantaneous speed

1. The instantaneous speed of an object is defined as the speed of that object at a particular or specific instant of time while its speed is continuously changing.
2. The speed displayed on a car’s speedometer is the speed at that particular instant or moment — the instantaneous speed.
3. Instantaneous speed is the speed calculated in an infinitesimal amount of time.

Mathematical Expression

1. $∆v=\underset{t\to 0}{\lim }\frac{∆s}{∆t}$
2. $∆v$ is the instantaneous speed or velocity.
3. $∆s$ is the infinitesimal distance and $∆t$is the infinitesimal time.