The SI unit of average velocity is
A. m/s
B. km/s
D. cm/s
E. mm/s

Hint: Average velocity is the ratio of total displacement to the total time taken for the travel. The average velocity and velocity have the same units. Using fundamental quantities we can solve the above question.

Complete Step-by-Step solution:
The average velocity is the total displacement per total time.
The SI unit of displacement is meter and that of time is seconds. Therefore, the SI unit of average velocity is,
\[\Rightarrow \dfrac{m}{s}=m/s\]
So, the correct option is B.

Additional information:
To calculate average velocity we need final \[({{x}_{f}})\] and initial position \[({{x}_{i}})\] according to a reference and the time taken for that motion \[({{t}_{f}}-{{t}_{i}})\].
\[\Delta v=\dfrac{{{x}_{f}}-{{x}_{i}}}{{{t}_{f}}-{{t}_{i}}}\]
Speed and velocity are similar since both are measuring how fast something is moving. Even though they are similar, they have slight differences. The velocity includes the direction motion but speed does not. Like this, average velocity and average speed shows difference. Average velocity uses displacement while average speed uses distance for the calculation.
Kinematics is a discipline in science and they will describe the motion without regarding the causes of it. There are four equations of kinematic and they can be used to predict the unknown information about the motion of an object from the known information.
1. \[v=u+at\]
2. \[S=ut+\dfrac{1}{2}a{{t}^{2}}\]
3. \[S=\dfrac{(u+v)t}{2}\]
4. \[{{v}^{2}}={{u}^{2}}+2aS\]
In these equations v is the final velocity, u is the initial velocity, t is the time taken for the movement, a is the acceleration and S Is the displacement.

Note: Average velocity uses total displacement and average speed uses distance for the calculation. However, their units are the same. Since they are measured in the same magnitude, fundamental quantities.