Question

What is the speed at any instant of time is known as?

Answer 1

Step 1. Instantaneous speed:

1. The instantaneous speed of an object is defined as the speed of object at a particular moment of time.
2. If the direction is also included with the speed, then it will be instantaneous velocity.
3. The mathematical expression for instantaneous speed is $S_i=\frac{ds}{dt}$, where $S_i$ = instantaneous speed, $ds$= change in distance, $dt$= time interval.
4. It is a scalar quantity.

Step 2. SI unit :

1. $m/s$ is the SI unit of instantaneous speed.
2. The dimension of instantaneous speed is $\left[M{L}^1{T}^{-1}\right]$

Step 3. An illustrative diagram of the instantaneous speed